SUBROUTINE DA7SST(IV, LIV, LV, V) C C *** ASSESS CANDIDATE STEP (***SOL VERSION 2.3) *** C INTEGER LIV, LV INTEGER IV(LIV) DOUBLE PRECISION V(LV) C C *** PURPOSE *** C C THIS SUBROUTINE IS CALLED BY AN UNCONSTRAINED MINIMIZATION C ROUTINE TO ASSESS THE NEXT CANDIDATE STEP. IT MAY RECOMMEND ONE C OF SEVERAL COURSES OF ACTION, SUCH AS ACCEPTING THE STEP, RECOM- C PUTING IT USING THE SAME OR A NEW QUADRATIC MODEL, OR HALTING DUE C TO CONVERGENCE OR FALSE CONVERGENCE. SEE THE RETURN CODE LISTING C BELOW. C C-------------------------- PARAMETER USAGE -------------------------- C C IV (I/O) INTEGER PARAMETER AND SCRATCH VECTOR -- SEE DESCRIPTION C BELOW OF IV VALUES REFERENCED. C LIV (IN) LENGTH OF IV ARRAY. C LV (IN) LENGTH OF V ARRAY. C V (I/O) REAL PARAMETER AND SCRATCH VECTOR -- SEE DESCRIPTION C BELOW OF V VALUES REFERENCED. C C *** IV VALUES REFERENCED *** C C IV(IRC) (I/O) ON INPUT FOR THE FIRST STEP TRIED IN A NEW ITERATION, C IV(IRC) SHOULD BE SET TO 3 OR 4 (THE VALUE TO WHICH IT IS C SET WHEN STEP IS DEFINITELY TO BE ACCEPTED). ON INPUT C AFTER STEP HAS BEEN RECOMPUTED, IV(IRC) SHOULD BE C UNCHANGED SINCE THE PREVIOUS RETURN OF DA7SST. C ON OUTPUT, IV(IRC) IS A RETURN CODE HAVING ONE OF THE C FOLLOWING VALUES... C 1 = SWITCH MODELS OR TRY SMALLER STEP. C 2 = SWITCH MODELS OR ACCEPT STEP. C 3 = ACCEPT STEP AND DETERMINE V(RADFAC) BY GRADIENT C TESTS. C 4 = ACCEPT STEP, V(RADFAC) HAS BEEN DETERMINED. C 5 = RECOMPUTE STEP (USING THE SAME MODEL). C 6 = RECOMPUTE STEP WITH RADIUS = V(LMAXS) BUT DO NOT C EVAULATE THE OBJECTIVE FUNCTION. C 7 = X-CONVERGENCE (SEE V(XCTOL)). C 8 = RELATIVE FUNCTION CONVERGENCE (SEE V(RFCTOL)). C 9 = BOTH X- AND RELATIVE FUNCTION CONVERGENCE. C 10 = ABSOLUTE FUNCTION CONVERGENCE (SEE V(AFCTOL)). C 11 = SINGULAR CONVERGENCE (SEE V(LMAXS)). C 12 = FALSE CONVERGENCE (SEE V(XFTOL)). C 13 = IV(IRC) WAS OUT OF RANGE ON INPUT. C RETURN CODE I HAS PRECDENCE OVER I+1 FOR I = 9, 10, 11. C IV(MLSTGD) (I/O) SAVED VALUE OF IV(MODEL). C IV(MODEL) (I/O) ON INPUT, IV(MODEL) SHOULD BE AN INTEGER IDENTIFYING C THE CURRENT QUADRATIC MODEL OF THE OBJECTIVE FUNCTION. C IF A PREVIOUS STEP YIELDED A BETTER FUNCTION REDUCTION, C THEN IV(MODEL) WILL BE SET TO IV(MLSTGD) ON OUTPUT. C IV(NFCALL) (IN) INVOCATION COUNT FOR THE OBJECTIVE FUNCTION. C IV(NFGCAL) (I/O) VALUE OF IV(NFCALL) AT STEP THAT GAVE THE BIGGEST C FUNCTION REDUCTION THIS ITERATION. IV(NFGCAL) REMAINS C UNCHANGED UNTIL A FUNCTION REDUCTION IS OBTAINED. C IV(RADINC) (I/O) THE NUMBER OF RADIUS INCREASES (OR MINUS THE NUMBER C OF DECREASES) SO FAR THIS ITERATION. C IV(RESTOR) (OUT) SET TO 1 IF V(F) HAS BEEN RESTORED AND X SHOULD BE C RESTORED TO ITS INITIAL VALUE, TO 2 IF X SHOULD BE SAVED, C TO 3 IF X SHOULD BE RESTORED FROM THE SAVED VALUE, AND TO C 0 OTHERWISE. C IV(STAGE) (I/O) COUNT OF THE NUMBER OF MODELS TRIED SO FAR IN THE C CURRENT ITERATION. C IV(STGLIM) (IN) MAXIMUM NUMBER OF MODELS TO CONSIDER. C IV(SWITCH) (OUT) SET TO 0 UNLESS A NEW MODEL IS BEING TRIED AND IT C GIVES A SMALLER FUNCTION VALUE THAN THE PREVIOUS MODEL, C IN WHICH CASE DA7SST SETS IV(SWITCH) = 1. C IV(TOOBIG) (IN) IS NONZERO IF STEP WAS TOO BIG (E.G. IF IT CAUSED C OVERFLOW). C IV(XIRC) (I/O) VALUE THAT IV(IRC) WOULD HAVE IN THE ABSENCE OF C CONVERGENCE, FALSE CONVERGENCE, AND OVERSIZED STEPS. C C *** V VALUES REFERENCED *** C C V(AFCTOL) (IN) ABSOLUTE FUNCTION CONVERGENCE TOLERANCE. IF THE C ABSOLUTE VALUE OF THE CURRENT FUNCTION VALUE V(F) IS LESS C THAN V(AFCTOL) AND DA7SST DOES NOT RETURN WITH C IV(IRC) = 11, THEN DA7SST RETURNS WITH IV(IRC) = 10. C V(DECFAC) (IN) FACTOR BY WHICH TO DECREASE RADIUS WHEN IV(TOOBIG) IS C NONZERO. C V(DSTNRM) (IN) THE 2-NORM OF D*STEP. C V(DSTSAV) (I/O) VALUE OF V(DSTNRM) ON SAVED STEP. C V(DST0) (IN) THE 2-NORM OF D TIMES THE NEWTON STEP (WHEN DEFINED, C I.E., FOR V(NREDUC) .GE. 0). C V(F) (I/O) ON BOTH INPUT AND OUTPUT, V(F) IS THE OBJECTIVE FUNC- C TION VALUE AT X. IF X IS RESTORED TO A PREVIOUS VALUE, C THEN V(F) IS RESTORED TO THE CORRESPONDING VALUE. C V(FDIF) (OUT) THE FUNCTION REDUCTION V(F0) - V(F) (FOR THE OUTPUT C VALUE OF V(F) IF AN EARLIER STEP GAVE A BIGGER FUNCTION C DECREASE, AND FOR THE INPUT VALUE OF V(F) OTHERWISE). C V(FLSTGD) (I/O) SAVED VALUE OF V(F). C V(F0) (IN) OBJECTIVE FUNCTION VALUE AT START OF ITERATION. C V(GTSLST) (I/O) VALUE OF V(GTSTEP) ON SAVED STEP. C V(GTSTEP) (IN) INNER PRODUCT BETWEEN STEP AND GRADIENT. C V(INCFAC) (IN) MINIMUM FACTOR BY WHICH TO INCREASE RADIUS. C V(LMAXS) (IN) MAXIMUM REASONABLE STEP SIZE (AND INITIAL STEP BOUND). C IF THE ACTUAL FUNCTION DECREASE IS NO MORE THAN TWICE C WHAT WAS PREDICTED, IF A RETURN WITH IV(IRC) = 7, 8, OR 9 C DOES NOT OCCUR, IF V(DSTNRM) .GT. V(LMAXS) OR THE CURRENT C STEP IS A NEWTON STEP, AND IF C V(PREDUC) .LE. V(SCTOL) * ABS(V(F0)), THEN DA7SST RETURNS C WITH IV(IRC) = 11. IF SO DOING APPEARS WORTHWHILE, THEN C DA7SST REPEATS THIS TEST (DISALLOWING A FULL NEWTON STEP) C WITH V(PREDUC) COMPUTED FOR A STEP OF LENGTH V(LMAXS) C (BY A RETURN WITH IV(IRC) = 6). C V(NREDUC) (I/O) FUNCTION REDUCTION PREDICTED BY QUADRATIC MODEL FOR C NEWTON STEP. IF DA7SST IS CALLED WITH IV(IRC) = 6, I.E., C IF V(PREDUC) HAS BEEN COMPUTED WITH RADIUS = V(LMAXS) FOR C USE IN THE SINGULAR CONVERVENCE TEST, THEN V(NREDUC) IS C SET TO -V(PREDUC) BEFORE THE LATTER IS RESTORED. C V(PLSTGD) (I/O) VALUE OF V(PREDUC) ON SAVED STEP. C V(PREDUC) (I/O) FUNCTION REDUCTION PREDICTED BY QUADRATIC MODEL FOR C CURRENT STEP. C V(RADFAC) (OUT) FACTOR TO BE USED IN DETERMINING THE NEW RADIUS, C WHICH SHOULD BE V(RADFAC)*DST, WHERE DST IS EITHER THE C OUTPUT VALUE OF V(DSTNRM) OR THE 2-NORM OF C DIAG(NEWD)*STEP FOR THE OUTPUT VALUE OF STEP AND THE C UPDATED VERSION, NEWD, OF THE SCALE VECTOR D. FOR C IV(IRC) = 3, V(RADFAC) = 1.0 IS RETURNED. C V(RDFCMN) (IN) MINIMUM VALUE FOR V(RADFAC) IN TERMS OF THE INPUT C VALUE OF V(DSTNRM) -- SUGGESTED VALUE = 0.1. C V(RDFCMX) (IN) MAXIMUM VALUE FOR V(RADFAC) -- SUGGESTED VALUE = 4.0. C V(RELDX) (IN) SCALED RELATIVE CHANGE IN X CAUSED BY STEP, COMPUTED C (E.G.) BY FUNCTION DRLDST AS C MAX (D(I)*ABS(X(I)-X0(I)), 1 .LE. I .LE. P) / C MAX (D(I)*(ABS(X(I))+ABS(X0(I))), 1 .LE. I .LE. P). C V(RFCTOL) (IN) RELATIVE FUNCTION CONVERGENCE TOLERANCE. IF THE C ACTUAL FUNCTION REDUCTION IS AT MOST TWICE WHAT WAS PRE- C DICTED AND V(NREDUC) .LE. V(RFCTOL)*ABS(V(F0)), THEN C DA7SST RETURNS WITH IV(IRC) = 8 OR 9. C V(SCTOL) (IN) SINGULAR CONVERGENCE TOLERANCE -- SEE V(LMAXS). C V(STPPAR) (IN) MARQUARDT PARAMETER -- 0 MEANS FULL NEWTON STEP. C V(TUNER1) (IN) TUNING CONSTANT USED TO DECIDE IF THE FUNCTION C REDUCTION WAS MUCH LESS THAN EXPECTED. SUGGESTED C VALUE = 0.1. C V(TUNER2) (IN) TUNING CONSTANT USED TO DECIDE IF THE FUNCTION C REDUCTION WAS LARGE ENOUGH TO ACCEPT STEP. SUGGESTED C VALUE = 10**-4. C V(TUNER3) (IN) TUNING CONSTANT USED TO DECIDE IF THE RADIUS C SHOULD BE INCREASED. SUGGESTED VALUE = 0.75. C V(XCTOL) (IN) X-CONVERGENCE CRITERION. IF STEP IS A NEWTON STEP C (V(STPPAR) = 0) HAVING V(RELDX) .LE. V(XCTOL) AND GIVING C AT MOST TWICE THE PREDICTED FUNCTION DECREASE, THEN C DA7SST RETURNS IV(IRC) = 7 OR 9. C V(XFTOL) (IN) FALSE CONVERGENCE TOLERANCE. IF STEP GAVE NO OR ONLY C A SMALL FUNCTION DECREASE AND V(RELDX) .LE. V(XFTOL), C THEN DA7SST RETURNS WITH IV(IRC) = 12. C C------------------------------- NOTES ------------------------------- C C *** APPLICATION AND USAGE RESTRICTIONS *** C C THIS ROUTINE IS CALLED AS PART OF THE NL2SOL (NONLINEAR C LEAST-SQUARES) PACKAGE. IT MAY BE USED IN ANY UNCONSTRAINED C MINIMIZATION SOLVER THAT USES DOGLEG, GOLDFELD-QUANDT-TROTTER, C OR LEVENBERG-MARQUARDT STEPS. C C *** ALGORITHM NOTES *** C C SEE (1) FOR FURTHER DISCUSSION OF THE ASSESSING AND MODEL C SWITCHING STRATEGIES. WHILE NL2SOL CONSIDERS ONLY TWO MODELS, C DA7SST IS DESIGNED TO HANDLE ANY NUMBER OF MODELS. C C *** USAGE NOTES *** C C ON THE FIRST CALL OF AN ITERATION, ONLY THE I/O VARIABLES C STEP, X, IV(IRC), IV(MODEL), V(F), V(DSTNRM), V(GTSTEP), AND C V(PREDUC) NEED HAVE BEEN INITIALIZED. BETWEEN CALLS, NO I/O C VALUES EXECPT STEP, X, IV(MODEL), V(F) AND THE STOPPING TOLER- C ANCES SHOULD BE CHANGED. C AFTER A RETURN FOR CONVERGENCE OR FALSE CONVERGENCE, ONE CAN C CHANGE THE STOPPING TOLERANCES AND CALL DA7SST AGAIN, IN WHICH C CASE THE STOPPING TESTS WILL BE REPEATED. C C *** REFERENCES *** C C (1) DENNIS, J.E., JR., GAY, D.M., AND WELSCH, R.E. (1981), C AN ADAPTIVE NONLINEAR LEAST-SQUARES ALGORITHM, C ACM TRANS. MATH. SOFTWARE, VOL. 7, NO. 3. C C (2) POWELL, M.J.D. (1970) A FORTRAN SUBROUTINE FOR SOLVING C SYSTEMS OF NONLINEAR ALGEBRAIC EQUATIONS, IN NUMERICAL C METHODS FOR NONLINEAR ALGEBRAIC EQUATIONS, EDITED BY C P. RABINOWITZ, GORDON AND BREACH, LONDON. C C *** HISTORY *** C C JOHN DENNIS DESIGNED MUCH OF THIS ROUTINE, STARTING WITH C IDEAS IN (2). ROY WELSCH SUGGESTED THE MODEL SWITCHING STRATEGY. C DAVID GAY AND STEPHEN PETERS CAST THIS SUBROUTINE INTO A MORE C PORTABLE FORM (WINTER 1977), AND DAVID GAY CAST IT INTO ITS C PRESENT FORM (FALL 1978), WITH MINOR CHANGES TO THE SINGULAR C CONVERGENCE TEST IN MAY, 1984 (TO DEAL WITH FULL NEWTON STEPS). C C *** GENERAL *** C C THIS SUBROUTINE WAS WRITTEN IN CONNECTION WITH RESEARCH C SUPPORTED BY THE NATIONAL SCIENCE FOUNDATION UNDER GRANTS C MCS-7600324, DCR75-10143, 76-14311DSS, MCS76-11989, AND C MCS-7906671. C C------------------------ EXTERNAL QUANTITIES ------------------------ C C *** NO EXTERNAL FUNCTIONS AND SUBROUTINES *** C C-------------------------- LOCAL VARIABLES -------------------------- C LOGICAL GOODX INTEGER I, NFC DOUBLE PRECISION EMAX, EMAXS, GTS, RFAC1, XMAX DOUBLE PRECISION HALF, ONE, ONEP2, TWO, ZERO C C *** SUBSCRIPTS FOR IV AND V *** C INTEGER AFCTOL, DECFAC, DSTNRM, DSTSAV, DST0, F, FDIF, FLSTGD, F0, 1 GTSLST, GTSTEP, INCFAC, IRC, LMAXS, MLSTGD, MODEL, NFCALL, 2 NFGCAL, NREDUC, PLSTGD, PREDUC, RADFAC, RADINC, RDFCMN, 3 RDFCMX, RELDX, RESTOR, RFCTOL, SCTOL, STAGE, STGLIM, 4 STPPAR, SWITCH, TOOBIG, TUNER1, TUNER2, TUNER3, XCTOL, 5 XFTOL, XIRC C C *** DATA INITIALIZATIONS *** C PARAMETER (HALF=0.5D+0, ONE=1.D+0, ONEP2=1.2D+0, TWO=2.D+0, 1 ZERO=0.D+0) C PARAMETER (IRC=29, MLSTGD=32, MODEL=5, NFCALL=6, NFGCAL=7, 1 RADINC=8, RESTOR=9, STAGE=10, STGLIM=11, SWITCH=12, 2 TOOBIG=2, XIRC=13) PARAMETER (AFCTOL=31, DECFAC=22, DSTNRM=2, DST0=3, DSTSAV=18, 1 F=10, FDIF=11, FLSTGD=12, F0=13, GTSLST=14, GTSTEP=4, 2 INCFAC=23, LMAXS=36, NREDUC=6, PLSTGD=15, PREDUC=7, 3 RADFAC=16, RDFCMN=24, RDFCMX=25, RELDX=17, RFCTOL=32, 4 SCTOL=37, STPPAR=5, TUNER1=26, TUNER2=27, TUNER3=28, 5 XCTOL=33, XFTOL=34) C C+++++++++++++++++++++++++++++++ BODY ++++++++++++++++++++++++++++++++ C NFC = IV(NFCALL) IV(SWITCH) = 0 IV(RESTOR) = 0 RFAC1 = ONE GOODX = .TRUE. I = IV(IRC) IF (I .GE. 1 .AND. I .LE. 12) 1 GO TO (20,30,10,10,40,280,220,220,220,220,220,170), I IV(IRC) = 13 GO TO 999 C C *** INITIALIZE FOR NEW ITERATION *** C 10 IV(STAGE) = 1 IV(RADINC) = 0 V(FLSTGD) = V(F0) IF (IV(TOOBIG) .EQ. 0) GO TO 110 IV(STAGE) = -1 IV(XIRC) = I GO TO 60 C C *** STEP WAS RECOMPUTED WITH NEW MODEL OR SMALLER RADIUS *** C *** FIRST DECIDE WHICH *** C 20 IF (IV(MODEL) .NE. IV(MLSTGD)) GO TO 30 C *** OLD MODEL RETAINED, SMALLER RADIUS TRIED *** C *** DO NOT CONSIDER ANY MORE NEW MODELS THIS ITERATION *** IV(STAGE) = IV(STGLIM) IV(RADINC) = -1 GO TO 110 C C *** A NEW MODEL IS BEING TRIED. DECIDE WHETHER TO KEEP IT. *** C 30 IV(STAGE) = IV(STAGE) + 1 C C *** NOW WE ADD THE POSSIBILTIY THAT STEP WAS RECOMPUTED WITH *** C *** THE SAME MODEL, PERHAPS BECAUSE OF AN OVERSIZED STEP. *** C 40 IF (IV(STAGE) .GT. 0) GO TO 50 C C *** STEP WAS RECOMPUTED BECAUSE IT WAS TOO BIG. *** C IF (IV(TOOBIG) .NE. 0) GO TO 60 C C *** RESTORE IV(STAGE) AND PICK UP WHERE WE LEFT OFF. *** C IV(STAGE) = -IV(STAGE) I = IV(XIRC) GO TO (20, 30, 110, 110, 70), I C 50 IF (IV(TOOBIG) .EQ. 0) GO TO 70 C C *** HANDLE OVERSIZE STEP *** C IF (IV(RADINC) .GT. 0) GO TO 80 IV(STAGE) = -IV(STAGE) IV(XIRC) = IV(IRC) C 60 V(RADFAC) = V(DECFAC) IV(RADINC) = IV(RADINC) - 1 IV(IRC) = 5 IV(RESTOR) = 1 GO TO 999 C 70 IF (V(F) .LT. V(FLSTGD)) GO TO 110 C C *** THE NEW STEP IS A LOSER. RESTORE OLD MODEL. *** C IF (IV(MODEL) .EQ. IV(MLSTGD)) GO TO 80 IV(MODEL) = IV(MLSTGD) IV(SWITCH) = 1 C C *** RESTORE STEP, ETC. ONLY IF A PREVIOUS STEP DECREASED V(F). C 80 IF (V(FLSTGD) .GE. V(F0)) GO TO 110 IV(RESTOR) = 1 V(F) = V(FLSTGD) V(PREDUC) = V(PLSTGD) V(GTSTEP) = V(GTSLST) IF (IV(SWITCH) .EQ. 0) RFAC1 = V(DSTNRM) / V(DSTSAV) V(DSTNRM) = V(DSTSAV) NFC = IV(NFGCAL) GOODX = .FALSE. C 110 V(FDIF) = V(F0) - V(F) IF (V(FDIF) .GT. V(TUNER2) * V(PREDUC)) GO TO 140 IF (IV(RADINC) .GT. 0) GO TO 140 C C *** NO (OR ONLY A TRIVIAL) FUNCTION DECREASE C *** -- SO TRY NEW MODEL OR SMALLER RADIUS C IF (V(F) .LT. V(F0)) GO TO 120 IV(MLSTGD) = IV(MODEL) V(FLSTGD) = V(F) V(F) = V(F0) IV(RESTOR) = 1 GO TO 130 120 IV(NFGCAL) = NFC 130 IV(IRC) = 1 IF (IV(STAGE) .LT. IV(STGLIM)) GO TO 160 IV(IRC) = 5 IV(RADINC) = IV(RADINC) - 1 GO TO 160 C C *** NONTRIVIAL FUNCTION DECREASE ACHIEVED *** C 140 IV(NFGCAL) = NFC RFAC1 = ONE V(DSTSAV) = V(DSTNRM) IF (V(FDIF) .GT. V(PREDUC)*V(TUNER1)) GO TO 190 C C *** DECREASE WAS MUCH LESS THAN PREDICTED -- EITHER CHANGE MODELS C *** OR ACCEPT STEP WITH DECREASED RADIUS. C IF (IV(STAGE) .GE. IV(STGLIM)) GO TO 150 C *** CONSIDER SWITCHING MODELS *** IV(IRC) = 2 GO TO 160 C C *** ACCEPT STEP WITH DECREASED RADIUS *** C 150 IV(IRC) = 4 C C *** SET V(RADFAC) TO FLETCHER*S DECREASE FACTOR *** C 160 IV(XIRC) = IV(IRC) EMAX = V(GTSTEP) + V(FDIF) V(RADFAC) = HALF * RFAC1 IF (EMAX .LT. V(GTSTEP)) V(RADFAC) = RFAC1 * MAX(V(RDFCMN), 1 HALF * V(GTSTEP)/EMAX) C C *** DO FALSE CONVERGENCE TEST *** C 170 IF (V(RELDX) .LE. V(XFTOL)) GO TO 180 IV(IRC) = IV(XIRC) IF (V(F) .LT. V(F0)) GO TO 200 GO TO 230 C 180 IV(IRC) = 12 GO TO 240 C C *** HANDLE GOOD FUNCTION DECREASE *** C 190 IF (V(FDIF) .LT. (-V(TUNER3) * V(GTSTEP))) GO TO 210 C C *** INCREASING RADIUS LOOKS WORTHWHILE. SEE IF WE JUST C *** RECOMPUTED STEP WITH A DECREASED RADIUS OR RESTORED STEP C *** AFTER RECOMPUTING IT WITH A LARGER RADIUS. C IF (IV(RADINC) .LT. 0) GO TO 210 IF (IV(RESTOR) .EQ. 1) GO TO 210 C C *** WE DID NOT. TRY A LONGER STEP UNLESS THIS WAS A NEWTON C *** STEP. C V(RADFAC) = V(RDFCMX) GTS = V(GTSTEP) IF (V(FDIF) .LT. (HALF/V(RADFAC) - ONE) * GTS) 1 V(RADFAC) = MAX(V(INCFAC), HALF*GTS/(GTS + V(FDIF))) IV(IRC) = 4 IF (V(STPPAR) .EQ. ZERO) GO TO 230 IF (V(DST0) .GE. ZERO .AND. (V(DST0) .LT. TWO*V(DSTNRM) 1 .OR. V(NREDUC) .LT. ONEP2*V(FDIF))) GO TO 230 C *** STEP WAS NOT A NEWTON STEP. RECOMPUTE IT WITH C *** A LARGER RADIUS. IV(IRC) = 5 IV(RADINC) = IV(RADINC) + 1 C C *** SAVE VALUES CORRESPONDING TO GOOD STEP *** C 200 V(FLSTGD) = V(F) IV(MLSTGD) = IV(MODEL) IF (IV(RESTOR) .NE. 1) IV(RESTOR) = 2 V(DSTSAV) = V(DSTNRM) IV(NFGCAL) = NFC V(PLSTGD) = V(PREDUC) V(GTSLST) = V(GTSTEP) GO TO 230 C C *** ACCEPT STEP WITH RADIUS UNCHANGED *** C 210 V(RADFAC) = ONE IV(IRC) = 3 GO TO 230 C C *** COME HERE FOR A RESTART AFTER CONVERGENCE *** C 220 IV(IRC) = IV(XIRC) IF (V(DSTSAV) .GE. ZERO) GO TO 240 IV(IRC) = 12 GO TO 240 C C *** PERFORM CONVERGENCE TESTS *** C 230 IV(XIRC) = IV(IRC) 240 IF (IV(RESTOR) .EQ. 1 .AND. V(FLSTGD) .LT. V(F0)) IV(RESTOR) = 3 IF ( ABS(V(F)) .LT. V(AFCTOL)) IV(IRC) = 10 IF (HALF * V(FDIF) .GT. V(PREDUC)) GO TO 999 EMAX = V(RFCTOL) * ABS(V(F0)) EMAXS = V(SCTOL) * ABS(V(F0)) IF (V(PREDUC) .LE. EMAXS .AND. (V(DSTNRM) .GT. V(LMAXS) .OR. 1 V(STPPAR) .EQ. ZERO)) IV(IRC) = 11 IF (V(DST0) .LT. ZERO) GO TO 250 I = 0 IF ((V(NREDUC) .GT. ZERO .AND. V(NREDUC) .LE. EMAX) .OR. 1 (V(NREDUC) .EQ. ZERO. AND. V(PREDUC) .EQ. ZERO)) I = 2 IF (V(STPPAR) .EQ. ZERO .AND. V(RELDX) .LE. V(XCTOL) 1 .AND. GOODX) I = I + 1 IF (I .GT. 0) IV(IRC) = I + 6 C C *** CONSIDER RECOMPUTING STEP OF LENGTH V(LMAXS) FOR SINGULAR C *** CONVERGENCE TEST. C 250 IF (IV(IRC) .GT. 5 .AND. IV(IRC) .NE. 12) GO TO 999 IF (V(STPPAR) .EQ. ZERO) GO TO 999 IF (V(DSTNRM) .GT. V(LMAXS)) GO TO 260 IF (V(PREDUC) .GE. EMAXS) GO TO 999 IF (V(DST0) .LE. ZERO) GO TO 270 IF (HALF * V(DST0) .LE. V(LMAXS)) GO TO 999 GO TO 270 260 IF (HALF * V(DSTNRM) .LE. V(LMAXS)) GO TO 999 XMAX = V(LMAXS) / V(DSTNRM) IF (XMAX * (TWO - XMAX) * V(PREDUC) .GE. EMAXS) GO TO 999 270 IF (V(NREDUC) .LT. ZERO) GO TO 290 C C *** RECOMPUTE V(PREDUC) FOR USE IN SINGULAR CONVERGENCE TEST *** C V(GTSLST) = V(GTSTEP) V(DSTSAV) = V(DSTNRM) IF (IV(IRC) .EQ. 12) V(DSTSAV) = -V(DSTSAV) V(PLSTGD) = V(PREDUC) I = IV(RESTOR) IV(RESTOR) = 2 IF (I .EQ. 3) IV(RESTOR) = 0 IV(IRC) = 6 GO TO 999 C C *** PERFORM SINGULAR CONVERGENCE TEST WITH RECOMPUTED V(PREDUC) *** C 280 V(GTSTEP) = V(GTSLST) V(DSTNRM) = ABS(V(DSTSAV)) IV(IRC) = IV(XIRC) IF (V(DSTSAV) .LE. ZERO) IV(IRC) = 12 V(NREDUC) = -V(PREDUC) V(PREDUC) = V(PLSTGD) IV(RESTOR) = 3 290 IF (-V(NREDUC) .LE. V(SCTOL) * ABS(V(F0))) IV(IRC) = 11 C 999 RETURN C C *** LAST LINE OF DA7SST FOLLOWS *** END DOUBLE PRECISION FUNCTION DD7TPR(P, X, Y) C C *** RETURN THE INNER PRODUCT OF THE P-VECTORS X AND Y. *** C INTEGER P DOUBLE PRECISION X(P), Y(P) C INTEGER I C *** ACTIVATE THE *'ED COMMENT LINES BELOW IF UNDERFLOW IS A PROBLEM. C *** DR7MDC(2) RETURNS A MACHINE-DEPENDENT CONSTANT, SQTETA, WHICH C *** IS SLIGHTLY LARGER THAN THE SMALLEST POSITIVE NUMBER THAT C *** CAN BE SQUARED WITHOUT UNDERFLOWING. C * DOUBLE PRECISION DR7MDC * EXTERNAL DR7MDC DOUBLE PRECISION ONE, ZERO PARAMETER (ONE=1.D+0, ZERO=0.D+0) * DOUBLE PRECISION SQTETA, T * DATA SQTETA/0.D+0/ C DD7TPR = ZERO * IF (P .LE. 0) GO TO 999 * IF (SQTETA .EQ. ZERO) SQTETA = DR7MDC(2) DO 20 I = 1, P * T = DMAX1(DABS(X(I)), DABS(Y(I))) * IF (T .GT. ONE) GO TO 10 * IF (T .LT. SQTETA) GO TO 20 * T = (X(I)/SQTETA)*Y(I) * IF (DABS(T) .LT. SQTETA) GO TO 20 10 DD7TPR = DD7TPR + X(I)*Y(I) 20 CONTINUE C 999 RETURN C *** LAST LINE OF DD7TPR FOLLOWS *** END SUBROUTINE DD7UP5(D, IV, LIV, LV, P, PS, V) C C *** UPDATE SCALE VECTOR D FOR DG7LIT *** C C *** PARAMETER DECLARATIONS *** C INTEGER LIV, LV, P, PS INTEGER IV(LIV) DOUBLE PRECISION D(P), V(LV) C C *** LOCAL VARIABLES *** C INTEGER D0, HII, I, JTOLI, JTOL0, R1I, S1 DOUBLE PRECISION T, VDFAC C C *** CONSTANTS *** DOUBLE PRECISION ZERO C C *** EXTERNAL FUNCTIONS *** C EXTERNAL DD7TPR DOUBLE PRECISION DD7TPR C C *** SUBSCRIPTS FOR IV AND V *** C INTEGER DFAC, DTYPE, HC, JTOL, NITER, RMAT, S PARAMETER (DFAC=41, DTYPE=16, HC=71, JTOL=59, NITER=31, RMAT=78, 1 S=62) C PARAMETER (ZERO=0.D+0) C C *** BODY *** C IF (IV(DTYPE) .NE. 1 .AND. IV(NITER) .GT. 0) GO TO 999 R1I = IV(RMAT) HII = IV(HC) - 1 VDFAC = V(DFAC) JTOL0 = IV(JTOL) - 1 D0 = JTOL0 + P S1 = IV(S) - 1 DO 30 I = 1, P IF (R1I .LE. 0) GO TO 10 T = DD7TPR(I, V(R1I), V(R1I)) R1I = R1I + I GO TO 20 10 HII = HII + I T = ABS(V(HII)) 20 S1 = S1 + I IF (I .LE. PS) T = T + MAX(V(S1), ZERO) T = SQRT(T) JTOLI = JTOL0 + I D0 = D0 + 1 IF (T .LT. V(JTOLI)) T = MAX(V(D0), V(JTOLI)) D(I) = MAX(VDFAC*D(I), T) 30 CONTINUE C 999 RETURN C *** LAST LINE OF DD7UP5 FOLLOWS *** END SUBROUTINE DG7QTS(D, DIG, DIHDI, KA, L, P, STEP, V, W) C C *** COMPUTE GOLDFELD-QUANDT-TROTTER STEP BY MORE-HEBDEN TECHNIQUE *** C *** (NL2SOL VERSION 2.2), MODIFIED A LA MORE AND SORENSEN *** C C *** PARAMETER DECLARATIONS *** C INTEGER KA, P DOUBLE PRECISION D(P), DIG(P), DIHDI(1), L(1), V(21), STEP(P), 1 W(1) C DIMENSION DIHDI(P*(P+1)/2), L(P*(P+1)/2), W(4*P+7) C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** PURPOSE *** C C GIVEN THE (COMPACTLY STORED) LOWER TRIANGLE OF A SCALED C HESSIAN (APPROXIMATION) AND A NONZERO SCALED GRADIENT VECTOR, C THIS SUBROUTINE COMPUTES A GOLDFELD-QUANDT-TROTTER STEP OF C APPROXIMATE LENGTH V(RADIUS) BY THE MORE-HEBDEN TECHNIQUE. IN C OTHER WORDS, STEP IS COMPUTED TO (APPROXIMATELY) MINIMIZE C PSI(STEP) = (G**T)*STEP + 0.5*(STEP**T)*H*STEP SUCH THAT THE C 2-NORM OF D*STEP IS AT MOST (APPROXIMATELY) V(RADIUS), WHERE C G IS THE GRADIENT, H IS THE HESSIAN, AND D IS A DIAGONAL C SCALE MATRIX WHOSE DIAGONAL IS STORED IN THE PARAMETER D. C (DG7QTS ASSUMES DIG = D**-1 * G AND DIHDI = D**-1 * H * D**-1.) C C *** PARAMETER DESCRIPTION *** C C D (IN) = THE SCALE VECTOR, I.E. THE DIAGONAL OF THE SCALE C MATRIX D MENTIONED ABOVE UNDER PURPOSE. C DIG (IN) = THE SCALED GRADIENT VECTOR, D**-1 * G. IF G = 0, THEN C STEP = 0 AND V(STPPAR) = 0 ARE RETURNED. C DIHDI (IN) = LOWER TRIANGLE OF THE SCALED HESSIAN (APPROXIMATION), C I.E., D**-1 * H * D**-1, STORED COMPACTLY BY ROWS., I.E., C IN THE ORDER (1,1), (2,1), (2,2), (3,1), (3,2), ETC. C KA (I/O) = THE NUMBER OF HEBDEN ITERATIONS (SO FAR) TAKEN TO DETER- C MINE STEP. KA .LT. 0 ON INPUT MEANS THIS IS THE FIRST C ATTEMPT TO DETERMINE STEP (FOR THE PRESENT DIG AND DIHDI) C -- KA IS INITIALIZED TO 0 IN THIS CASE. OUTPUT WITH C KA = 0 (OR V(STPPAR) = 0) MEANS STEP = -(H**-1)*G. C L (I/O) = WORKSPACE OF LENGTH P*(P+1)/2 FOR CHOLESKY FACTORS. C P (IN) = NUMBER OF PARAMETERS -- THE HESSIAN IS A P X P MATRIX. C STEP (I/O) = THE STEP COMPUTED. C V (I/O) CONTAINS VARIOUS CONSTANTS AND VARIABLES DESCRIBED BELOW. C W (I/O) = WORKSPACE OF LENGTH 4*P + 6. C C *** ENTRIES IN V *** C C V(DGNORM) (I/O) = 2-NORM OF (D**-1)*G. C V(DSTNRM) (OUTPUT) = 2-NORM OF D*STEP. C V(DST0) (I/O) = 2-NORM OF D*(H**-1)*G (FOR POS. DEF. H ONLY), OR C OVERESTIMATE OF SMALLEST EIGENVALUE OF (D**-1)*H*(D**-1). C V(EPSLON) (IN) = MAX. REL. ERROR ALLOWED FOR PSI(STEP). FOR THE C STEP RETURNED, PSI(STEP) WILL EXCEED ITS OPTIMAL VALUE C BY LESS THAN -V(EPSLON)*PSI(STEP). SUGGESTED VALUE = 0.1. C V(GTSTEP) (OUT) = INNER PRODUCT BETWEEN G AND STEP. C V(NREDUC) (OUT) = PSI(-(H**-1)*G) = PSI(NEWTON STEP) (FOR POS. DEF. C H ONLY -- V(NREDUC) IS SET TO ZERO OTHERWISE). C V(PHMNFC) (IN) = TOL. (TOGETHER WITH V(PHMXFC)) FOR ACCEPTING STEP C (MORE*S SIGMA). THE ERROR V(DSTNRM) - V(RADIUS) MUST LIE C BETWEEN V(PHMNFC)*V(RADIUS) AND V(PHMXFC)*V(RADIUS). C V(PHMXFC) (IN) (SEE V(PHMNFC).) C SUGGESTED VALUES -- V(PHMNFC) = -0.25, V(PHMXFC) = 0.5. C V(PREDUC) (OUT) = PSI(STEP) = PREDICTED OBJ. FUNC. REDUCTION FOR STEP. C V(RADIUS) (IN) = RADIUS OF CURRENT (SCALED) TRUST REGION. C V(RAD0) (I/O) = VALUE OF V(RADIUS) FROM PREVIOUS CALL. C V(STPPAR) (I/O) IS NORMALLY THE MARQUARDT PARAMETER, I.E. THE ALPHA C DESCRIBED BELOW UNDER ALGORITHM NOTES. IF H + ALPHA*D**2 C (SEE ALGORITHM NOTES) IS (NEARLY) SINGULAR, HOWEVER, C THEN V(STPPAR) = -ALPHA. C C *** USAGE NOTES *** C C IF IT IS DESIRED TO RECOMPUTE STEP USING A DIFFERENT VALUE OF C V(RADIUS), THEN THIS ROUTINE MAY BE RESTARTED BY CALLING IT C WITH ALL PARAMETERS UNCHANGED EXCEPT V(RADIUS). (THIS EXPLAINS C WHY STEP AND W ARE LISTED AS I/O). ON AN INITIAL CALL (ONE WITH C KA .LT. 0), STEP AND W NEED NOT BE INITIALIZED AND ONLY COMPO- C NENTS V(EPSLON), V(STPPAR), V(PHMNFC), V(PHMXFC), V(RADIUS), AND C V(RAD0) OF V MUST BE INITIALIZED. C C *** ALGORITHM NOTES *** C C THE DESIRED G-Q-T STEP (REF. 2, 3, 4, 6) SATISFIES C (H + ALPHA*D**2)*STEP = -G FOR SOME NONNEGATIVE ALPHA SUCH THAT C H + ALPHA*D**2 IS POSITIVE SEMIDEFINITE. ALPHA AND STEP ARE C COMPUTED BY A SCHEME ANALOGOUS TO THE ONE DESCRIBED IN REF. 5. C ESTIMATES OF THE SMALLEST AND LARGEST EIGENVALUES OF THE HESSIAN C ARE OBTAINED FROM THE GERSCHGORIN CIRCLE THEOREM ENHANCED BY A C SIMPLE FORM OF THE SCALING DESCRIBED IN REF. 7. CASES IN WHICH C H + ALPHA*D**2 IS NEARLY (OR EXACTLY) SINGULAR ARE HANDLED BY C THE TECHNIQUE DISCUSSED IN REF. 2. IN THESE CASES, A STEP OF C (EXACT) LENGTH V(RADIUS) IS RETURNED FOR WHICH PSI(STEP) EXCEEDS C ITS OPTIMAL VALUE BY LESS THAN -V(EPSLON)*PSI(STEP). THE TEST C SUGGESTED IN REF. 6 FOR DETECTING THE SPECIAL CASE IS PERFORMED C ONCE TWO MATRIX FACTORIZATIONS HAVE BEEN DONE -- DOING SO SOONER C SEEMS TO DEGRADE THE PERFORMANCE OF OPTIMIZATION ROUTINES THAT C CALL THIS ROUTINE. C C *** FUNCTIONS AND SUBROUTINES CALLED *** C C DD7TPR - RETURNS INNER PRODUCT OF TWO VECTORS. C DL7ITV - APPLIES INVERSE-TRANSPOSE OF COMPACT LOWER TRIANG. MATRIX. C DL7IVM - APPLIES INVERSE OF COMPACT LOWER TRIANG. MATRIX. C DL7SRT - FINDS CHOLESKY FACTOR (OF COMPACTLY STORED LOWER TRIANG.). C DL7SVN - RETURNS APPROX. TO MIN. SING. VALUE OF LOWER TRIANG. MATRIX. C DR7MDC - RETURNS MACHINE-DEPENDENT CONSTANTS. C DV2NRM - RETURNS 2-NORM OF A VECTOR. C C *** REFERENCES *** C C 1. DENNIS, J.E., GAY, D.M., AND WELSCH, R.E. (1981), AN ADAPTIVE C NONLINEAR LEAST-SQUARES ALGORITHM, ACM TRANS. MATH. C SOFTWARE, VOL. 7, NO. 3. C 2. GAY, D.M. (1981), COMPUTING OPTIMAL LOCALLY CONSTRAINED STEPS, C SIAM J. SCI. STATIST. COMPUTING, VOL. 2, NO. 2, PP. C 186-197. C 3. GOLDFELD, S.M., QUANDT, R.E., AND TROTTER, H.F. (1966), C MAXIMIZATION BY QUADRATIC HILL-CLIMBING, ECONOMETRICA 34, C PP. 541-551. C 4. HEBDEN, M.D. (1973), AN ALGORITHM FOR MINIMIZATION USING EXACT C SECOND DERIVATIVES, REPORT T.P. 515, THEORETICAL PHYSICS C DIV., A.E.R.E. HARWELL, OXON., ENGLAND. C 5. MORE, J.J. (1978), THE LEVENBERG-MARQUARDT ALGORITHM, IMPLEMEN- C TATION AND THEORY, PP.105-116 OF SPRINGER LECTURE NOTES C IN MATHEMATICS NO. 630, EDITED BY G.A. WATSON, SPRINGER- C VERLAG, BERLIN AND NEW YORK. C 6. MORE, J.J., AND SORENSEN, D.C. (1981), COMPUTING A TRUST REGION C STEP, TECHNICAL REPORT ANL-81-83, ARGONNE NATIONAL LAB. C 7. VARGA, R.S. (1965), MINIMAL GERSCHGORIN SETS, PACIFIC J. MATH. 15, C PP. 719-729. C C *** GENERAL *** C C CODED BY DAVID M. GAY. C THIS SUBROUTINE WAS WRITTEN IN CONNECTION WITH RESEARCH C SUPPORTED BY THE NATIONAL SCIENCE FOUNDATION UNDER GRANTS C MCS-7600324, DCR75-10143, 76-14311DSS, MCS76-11989, AND C MCS-7906671. C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** LOCAL VARIABLES *** C LOGICAL RESTRT INTEGER DGGDMX, DIAG, DIAG0, DSTSAV, EMAX, EMIN, I, IM1, INC, IRC, 1 J, K, KALIM, KAMIN, K1, LK0, PHIPIN, Q, Q0, UK0, X DOUBLE PRECISION ALPHAK, AKI, AKK, DELTA, DST, EPS, GTSTA, LK, 1 OLDPHI, PHI, PHIMAX, PHIMIN, PSIFAC, RAD, RADSQ, 2 ROOT, SI, SK, SW, T, TWOPSI, T1, T2, UK, WI C C *** CONSTANTS *** DOUBLE PRECISION BIG, DGXFAC, EPSFAC, FOUR, HALF, KAPPA, NEGONE, 1 ONE, P001, SIX, THREE, TWO, ZERO C C *** EXTERNAL FUNCTIONS AND SUBROUTINES *** C DOUBLE PRECISION DD7TPR, DL7SVN, DR7MDC, DV2NRM EXTERNAL DD7TPR, DL7ITV, DL7IVM,DL7SRT, DL7SVN, DR7MDC, DV2NRM C C *** SUBSCRIPTS FOR V *** C INTEGER DGNORM, DSTNRM, DST0, EPSLON, GTSTEP, STPPAR, NREDUC, 1 PHMNFC, PHMXFC, PREDUC, RADIUS, RAD0 PARAMETER (DGNORM=1, DSTNRM=2, DST0=3, EPSLON=19, GTSTEP=4, 1 NREDUC=6, PHMNFC=20, PHMXFC=21, PREDUC=7, RADIUS=8, 2 RAD0=9, STPPAR=5) C PARAMETER (EPSFAC=50.0D+0, FOUR=4.0D+0, HALF=0.5D+0, 1 KAPPA=2.0D+0, NEGONE=-1.0D+0, ONE=1.0D+0, P001=1.0D-3, 2 SIX=6.0D+0, THREE=3.0D+0, TWO=2.0D+0, ZERO=0.0D+0) SAVE DGXFAC DATA BIG/0.D+0/, DGXFAC/0.D+0/ C C *** BODY *** C IF (BIG .LE. ZERO) BIG = DR7MDC(6) C C *** STORE LARGEST ABS. ENTRY IN (D**-1)*H*(D**-1) AT W(DGGDMX). DGGDMX = P + 1 C *** STORE GERSCHGORIN OVER- AND UNDERESTIMATES OF THE LARGEST C *** AND SMALLEST EIGENVALUES OF (D**-1)*H*(D**-1) AT W(EMAX) C *** AND W(EMIN) RESPECTIVELY. EMAX = DGGDMX + 1 EMIN = EMAX + 1 C *** FOR USE IN RECOMPUTING STEP, THE FINAL VALUES OF LK, UK, DST, C *** AND THE INVERSE DERIVATIVE OF MORE*S PHI AT 0 (FOR POS. DEF. C *** H) ARE STORED IN W(LK0), W(UK0), W(DSTSAV), AND W(PHIPIN) C *** RESPECTIVELY. LK0 = EMIN + 1 PHIPIN = LK0 + 1 UK0 = PHIPIN + 1 DSTSAV = UK0 + 1 C *** STORE DIAG OF (D**-1)*H*(D**-1) IN W(DIAG),...,W(DIAG0+P). DIAG0 = DSTSAV DIAG = DIAG0 + 1 C *** STORE -D*STEP IN W(Q),...,W(Q0+P). Q0 = DIAG0 + P Q = Q0 + 1 C *** ALLOCATE STORAGE FOR SCRATCH VECTOR X *** X = Q + P RAD = V(RADIUS) RADSQ = RAD**2 C *** PHITOL = MAX. ERROR ALLOWED IN DST = V(DSTNRM) = 2-NORM OF C *** D*STEP. PHIMAX = V(PHMXFC) * RAD PHIMIN = V(PHMNFC) * RAD PSIFAC = BIG T1 = TWO * V(EPSLON) / (THREE * (FOUR * (V(PHMNFC) + ONE) * 1 (KAPPA + ONE) + KAPPA + TWO) * RAD) IF (T1 .LT. BIG* MIN(RAD,ONE)) PSIFAC = T1 / RAD C *** OLDPHI IS USED TO DETECT LIMITS OF NUMERICAL ACCURACY. IF C *** WE RECOMPUTE STEP AND IT DOES NOT CHANGE, THEN WE ACCEPT IT. OLDPHI = ZERO EPS = V(EPSLON) IRC = 0 RESTRT = .FALSE. KALIM = KA + 50 C C *** START OR RESTART, DEPENDING ON KA *** C IF (KA .GE. 0) GO TO 290 C C *** FRESH START *** C K = 0 UK = NEGONE KA = 0 KALIM = 50 V(DGNORM) = DV2NRM(P, DIG) V(NREDUC) = ZERO V(DST0) = ZERO KAMIN = 3 IF (V(DGNORM) .EQ. ZERO) KAMIN = 0 C C *** STORE DIAG(DIHDI) IN W(DIAG0+1),...,W(DIAG0+P) *** C J = 0 DO 10 I = 1, P J = J + I K1 = DIAG0 + I W(K1) = DIHDI(J) 10 CONTINUE C C *** DETERMINE W(DGGDMX), THE LARGEST ELEMENT OF DIHDI *** C T1 = ZERO J = P * (P + 1) / 2 DO 20 I = 1, J T = ABS(DIHDI(I)) IF (T1 .LT. T) T1 = T 20 CONTINUE W(DGGDMX) = T1 C C *** TRY ALPHA = 0 *** C 30 CALL DL7SRT(1, P, L, DIHDI, IRC) IF (IRC .EQ. 0) GO TO 50 C *** INDEF. H -- UNDERESTIMATE SMALLEST EIGENVALUE, USE THIS C *** ESTIMATE TO INITIALIZE LOWER BOUND LK ON ALPHA. J = IRC*(IRC+1)/2 T = L(J) L(J) = ONE DO 40 I = 1, IRC 40 W(I) = ZERO W(IRC) = ONE CALL DL7ITV(IRC, W, L, W) T1 = DV2NRM(IRC, W) LK = -T / T1 / T1 V(DST0) = -LK IF (RESTRT) GO TO 210 GO TO 70 C C *** POSITIVE DEFINITE H -- COMPUTE UNMODIFIED NEWTON STEP. *** 50 LK = ZERO T = DL7SVN(P, L, W(Q), W(Q)) IF (T .GE. ONE) GO TO 60 IF (V(DGNORM) .GE. T*T*BIG) GO TO 70 60 CALL DL7IVM(P, W(Q), L, DIG) GTSTA = DD7TPR(P, W(Q), W(Q)) V(NREDUC) = HALF * GTSTA CALL DL7ITV(P, W(Q), L, W(Q)) DST = DV2NRM(P, W(Q)) V(DST0) = DST PHI = DST - RAD IF (PHI .LE. PHIMAX) GO TO 260 IF (RESTRT) GO TO 210 C C *** PREPARE TO COMPUTE GERSCHGORIN ESTIMATES OF LARGEST (AND C *** SMALLEST) EIGENVALUES. *** C 70 K = 0 DO 100 I = 1, P WI = ZERO IF (I .EQ. 1) GO TO 90 IM1 = I - 1 DO 80 J = 1, IM1 K = K + 1 T = ABS(DIHDI(K)) WI = WI + T W(J) = W(J) + T 80 CONTINUE 90 W(I) = WI K = K + 1 100 CONTINUE C C *** (UNDER-)ESTIMATE SMALLEST EIGENVALUE OF (D**-1)*H*(D**-1) *** C K = 1 T1 = W(DIAG) - W(1) IF (P .LE. 1) GO TO 120 DO 110 I = 2, P J = DIAG0 + I T = W(J) - W(I) IF (T .GE. T1) GO TO 110 T1 = T K = I 110 CONTINUE C 120 SK = W(K) J = DIAG0 + K AKK = W(J) K1 = K*(K-1)/2 + 1 INC = 1 T = ZERO DO 150 I = 1, P IF (I .EQ. K) GO TO 130 AKI = ABS(DIHDI(K1)) SI = W(I) J = DIAG0 + I T1 = HALF * (AKK - W(J) + SI - AKI) T1 = T1 + SQRT(T1*T1 + SK*AKI) IF (T .LT. T1) T = T1 IF (I .LT. K) GO TO 140 130 INC = I 140 K1 = K1 + INC 150 CONTINUE C W(EMIN) = AKK - T UK = V(DGNORM)/RAD - W(EMIN) IF (V(DGNORM) .EQ. ZERO) UK = UK + P001 + P001*UK IF (UK .LE. ZERO) UK = P001 C C *** COMPUTE GERSCHGORIN (OVER-)ESTIMATE OF LARGEST EIGENVALUE *** C K = 1 T1 = W(DIAG) + W(1) IF (P .LE. 1) GO TO 170 DO 160 I = 2, P J = DIAG0 + I T = W(J) + W(I) IF (T .LE. T1) GO TO 160 T1 = T K = I 160 CONTINUE C 170 SK = W(K) J = DIAG0 + K AKK = W(J) K1 = K*(K-1)/2 + 1 INC = 1 T = ZERO DO 200 I = 1, P IF (I .EQ. K) GO TO 180 AKI = ABS(DIHDI(K1)) SI = W(I) J = DIAG0 + I T1 = HALF * (W(J) + SI - AKI - AKK) T1 = T1 + SQRT(T1*T1 + SK*AKI) IF (T .LT. T1) T = T1 IF (I .LT. K) GO TO 190 180 INC = I 190 K1 = K1 + INC 200 CONTINUE C W(EMAX) = AKK + T LK = MAX(LK, V(DGNORM)/RAD - W(EMAX)) C C *** ALPHAK = CURRENT VALUE OF ALPHA (SEE ALG. NOTES ABOVE). WE C *** USE MORE*S SCHEME FOR INITIALIZING IT. ALPHAK = ABS(V(STPPAR)) * V(RAD0)/RAD ALPHAK = MIN(UK, MAX(ALPHAK, LK)) C IF (IRC .NE. 0) GO TO 210 C C *** COMPUTE L0 FOR POSITIVE DEFINITE H *** C CALL DL7IVM(P, W, L, W(Q)) T = DV2NRM(P, W) W(PHIPIN) = RAD / T / T LK = MAX(LK, PHI*W(PHIPIN)) C C *** SAFEGUARD ALPHAK AND ADD ALPHAK*I TO (D**-1)*H*(D**-1) *** C 210 KA = KA + 1 IF (-V(DST0) .GE. ALPHAK .OR. ALPHAK .LT. LK .OR. ALPHAK .GE. UK) 1 ALPHAK = UK * MAX(P001, SQRT(LK/UK)) IF (ALPHAK .LE. ZERO) ALPHAK = HALF * UK IF (ALPHAK .LE. ZERO) ALPHAK = UK K = 0 DO 220 I = 1, P K = K + I J = DIAG0 + I DIHDI(K) = W(J) + ALPHAK 220 CONTINUE C C *** TRY COMPUTING CHOLESKY DECOMPOSITION *** C CALL DL7SRT(1, P, L, DIHDI, IRC) IF (IRC .EQ. 0) GO TO 240 C C *** (D**-1)*H*(D**-1) + ALPHAK*I IS INDEFINITE -- OVERESTIMATE C *** SMALLEST EIGENVALUE FOR USE IN UPDATING LK *** C J = (IRC*(IRC+1))/2 T = L(J) L(J) = ONE DO 230 I = 1, IRC 230 W(I) = ZERO W(IRC) = ONE CALL DL7ITV(IRC, W, L, W) T1 = DV2NRM(IRC, W) LK = ALPHAK - T/T1/T1 V(DST0) = -LK IF (UK .LT. LK) UK = LK IF (ALPHAK .LT. LK) GO TO 210 C C *** NASTY CASE -- EXACT GERSCHGORIN BOUNDS. FUDGE LK, UK... C T = P001 * ALPHAK IF (T .LE. ZERO) T = P001 LK = ALPHAK + T IF (UK .LE. LK) UK = LK + T GO TO 210 C C *** ALPHAK MAKES (D**-1)*H*(D**-1) POSITIVE DEFINITE. C *** COMPUTE Q = -D*STEP, CHECK FOR CONVERGENCE. *** C 240 CALL DL7IVM(P, W(Q), L, DIG) GTSTA = DD7TPR(P, W(Q), W(Q)) CALL DL7ITV(P, W(Q), L, W(Q)) DST = DV2NRM(P, W(Q)) PHI = DST - RAD IF (PHI .LE. PHIMAX .AND. PHI .GE. PHIMIN) GO TO 270 IF (PHI .EQ. OLDPHI) GO TO 270 OLDPHI = PHI IF (PHI .LT. ZERO) GO TO 330 C C *** UNACCEPTABLE ALPHAK -- UPDATE LK, UK, ALPHAK *** C 250 IF (KA .GE. KALIM) GO TO 270 C *** THE FOLLOWING MIN IS NECESSARY BECAUSE OF RESTARTS *** IF (PHI .LT. ZERO) UK = MIN(UK, ALPHAK) C *** KAMIN = 0 ONLY IFF THE GRADIENT VANISHES *** IF (KAMIN .EQ. 0) GO TO 210 CALL DL7IVM(P, W, L, W(Q)) C *** THE FOLLOWING, COMMENTED CALCULATION OF ALPHAK IS SOMETIMES C *** SAFER BUT WORSE IN PERFORMANCE... C T1 = DST / DV2NRM(P, W) C ALPHAK = ALPHAK + T1 * (PHI/RAD) * T1 T1 = DV2NRM(P, W) ALPHAK = ALPHAK + (PHI/T1) * (DST/T1) * (DST/RAD) LK = MAX(LK, ALPHAK) ALPHAK = LK GO TO 210 C C *** ACCEPTABLE STEP ON FIRST TRY *** C 260 ALPHAK = ZERO C C *** SUCCESSFUL STEP IN GENERAL. COMPUTE STEP = -(D**-1)*Q *** C 270 DO 280 I = 1, P J = Q0 + I STEP(I) = -W(J)/D(I) 280 CONTINUE V(GTSTEP) = -GTSTA V(PREDUC) = HALF * ( ABS(ALPHAK)*DST*DST + GTSTA) GO TO 410 C C C *** RESTART WITH NEW RADIUS *** C 290 IF (V(DST0) .LE. ZERO .OR. V(DST0) - RAD .GT. PHIMAX) GO TO 310 C C *** PREPARE TO RETURN NEWTON STEP *** C RESTRT = .TRUE. KA = KA + 1 K = 0 DO 300 I = 1, P K = K + I J = DIAG0 + I DIHDI(K) = W(J) 300 CONTINUE UK = NEGONE GO TO 30 C 310 KAMIN = KA + 3 IF (V(DGNORM) .EQ. ZERO) KAMIN = 0 IF (KA .EQ. 0) GO TO 50 C DST = W(DSTSAV) ALPHAK = ABS(V(STPPAR)) PHI = DST - RAD T = V(DGNORM)/RAD UK = T - W(EMIN) IF (V(DGNORM) .EQ. ZERO) UK = UK + P001 + P001*UK IF (UK .LE. ZERO) UK = P001 IF (RAD .GT. V(RAD0)) GO TO 320 C C *** SMALLER RADIUS *** LK = ZERO IF (ALPHAK .GT. ZERO) LK = W(LK0) LK = MAX(LK, T - W(EMAX)) IF (V(DST0) .GT. ZERO) LK = MAX(LK, (V(DST0)-RAD)*W(PHIPIN)) GO TO 250 C C *** BIGGER RADIUS *** 320 IF (ALPHAK .GT. ZERO) UK = MIN(UK, W(UK0)) LK = MAX(ZERO, -V(DST0), T - W(EMAX)) IF (V(DST0) .GT. ZERO) LK = MAX(LK, (V(DST0)-RAD)*W(PHIPIN)) GO TO 250 C C *** DECIDE WHETHER TO CHECK FOR SPECIAL CASE... IN PRACTICE (FROM C *** THE STANDPOINT OF THE CALLING OPTIMIZATION CODE) IT SEEMS BEST C *** NOT TO CHECK UNTIL A FEW ITERATIONS HAVE FAILED -- HENCE THE C *** TEST ON KAMIN BELOW. C 330 DELTA = ALPHAK + MIN(ZERO, V(DST0)) TWOPSI = ALPHAK*DST*DST + GTSTA IF (KA .GE. KAMIN) GO TO 340 C *** IF THE TEST IN REF. 2 IS SATISFIED, FALL THROUGH TO HANDLE C *** THE SPECIAL CASE (AS SOON AS THE MORE-SORENSEN TEST DETECTS C *** IT). IF (PSIFAC .GE. BIG) GO TO 340 IF (DELTA .GE. PSIFAC*TWOPSI) GO TO 370 C C *** CHECK FOR THE SPECIAL CASE OF H + ALPHA*D**2 (NEARLY) C *** SINGULAR. USE ONE STEP OF INVERSE POWER METHOD WITH START C *** FROM DL7SVN TO OBTAIN APPROXIMATE EIGENVECTOR CORRESPONDING C *** TO SMALLEST EIGENVALUE OF (D**-1)*H*(D**-1). DL7SVN RETURNS C *** X AND W WITH L*W = X. C 340 T = DL7SVN(P, L, W(X), W) C C *** NORMALIZE W *** DO 350 I = 1, P 350 W(I) = T*W(I) C *** COMPLETE CURRENT INV. POWER ITER. -- REPLACE W BY (L**-T)*W. CALL DL7ITV(P, W, L, W) T2 = ONE/DV2NRM(P, W) DO 360 I = 1, P 360 W(I) = T2*W(I) T = T2 * T C C *** NOW W IS THE DESIRED APPROXIMATE (UNIT) EIGENVECTOR AND C *** T*X = ((D**-1)*H*(D**-1) + ALPHAK*I)*W. C SW = DD7TPR(P, W(Q), W) T1 = (RAD + DST) * (RAD - DST) ROOT = SQRT(SW*SW + T1) IF (SW .LT. ZERO) ROOT = -ROOT SI = T1 / (SW + ROOT) C C *** THE ACTUAL TEST FOR THE SPECIAL CASE... C IF ((T2*SI)**2 .LE. EPS*(DST**2 + ALPHAK*RADSQ)) GO TO 380 C C *** UPDATE UPPER BOUND ON SMALLEST EIGENVALUE (WHEN NOT POSITIVE) C *** (AS RECOMMENDED BY MORE AND SORENSEN) AND CONTINUE... C IF (V(DST0) .LE. ZERO) V(DST0) = MIN(V(DST0), T2**2 - ALPHAK) LK = MAX(LK, -V(DST0)) C C *** CHECK WHETHER WE CAN HOPE TO DETECT THE SPECIAL CASE IN C *** THE AVAILABLE ARITHMETIC. ACCEPT STEP AS IT IS IF NOT. C C *** IF NOT YET AVAILABLE, OBTAIN MACHINE DEPENDENT VALUE DGXFAC. 370 IF (DGXFAC .EQ. ZERO) DGXFAC = EPSFAC * DR7MDC(3) C IF (DELTA .GT. DGXFAC*W(DGGDMX)) GO TO 250 GO TO 270 C C *** SPECIAL CASE DETECTED... NEGATE ALPHAK TO INDICATE SPECIAL CASE C 380 ALPHAK = -ALPHAK V(PREDUC) = HALF * TWOPSI C C *** ACCEPT CURRENT STEP IF ADDING SI*W WOULD LEAD TO A C *** FURTHER RELATIVE REDUCTION IN PSI OF LESS THAN V(EPSLON)/3. C T1 = ZERO T = SI*(ALPHAK*SW - HALF*SI*(ALPHAK + T*DD7TPR(P,W(X),W))) IF (T .LT. EPS*TWOPSI/SIX) GO TO 390 V(PREDUC) = V(PREDUC) + T DST = RAD T1 = -SI 390 DO 400 I = 1, P J = Q0 + I W(J) = T1*W(I) - W(J) STEP(I) = W(J) / D(I) 400 CONTINUE V(GTSTEP) = DD7TPR(P, DIG, W(Q)) C C *** SAVE VALUES FOR USE IN A POSSIBLE RESTART *** C 410 V(DSTNRM) = DST V(STPPAR) = ALPHAK W(LK0) = LK W(UK0) = UK V(RAD0) = RAD W(DSTSAV) = DST C C *** RESTORE DIAGONAL OF DIHDI *** C J = 0 DO 420 I = 1, P J = J + I K = DIAG0 + I DIHDI(J) = W(K) 420 CONTINUE C 999 RETURN C C *** LAST LINE OF DG7QTS FOLLOWS *** END SUBROUTINE DITSUM(D, G, IV, LIV, LV, P, V, X) C C *** PRINT ITERATION SUMMARY FOR ***SOL (VERSION 2.3) *** C C *** PARAMETER DECLARATIONS *** C INTEGER LIV, LV, P INTEGER IV(LIV) DOUBLE PRECISION D(P), G(P), V(LV), X(P) C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** LOCAL VARIABLES *** C INTEGER ALG, I, IV1, M, NF, NG, OL, PU CHARACTER*4 MODEL1(6), MODEL2(6) DOUBLE PRECISION NRELDF, OLDF, PRELDF, RELDF, ZERO C C *** NO EXTERNAL FUNCTIONS OR SUBROUTINES *** C C *** SUBSCRIPTS FOR IV AND V *** C INTEGER ALGSAV, DSTNRM, F, FDIF, F0, NEEDHD, NFCALL, NFCOV, NGCOV, 1 NGCALL, NITER, NREDUC, OUTLEV, PREDUC, PRNTIT, PRUNIT, 2 RELDX, SOLPRT, STATPR, STPPAR, SUSED, X0PRT C C *** IV SUBSCRIPT VALUES *** C PARAMETER (ALGSAV=51, NEEDHD=36, NFCALL=6, NFCOV=52, NGCALL=30, 1 NGCOV=53, NITER=31, OUTLEV=19, PRNTIT=39, PRUNIT=21, 2 SOLPRT=22, STATPR=23, SUSED=64, X0PRT=24) C C *** V SUBSCRIPT VALUES *** C PARAMETER (DSTNRM=2, F=10, F0=13, FDIF=11, NREDUC=6, PREDUC=7, 1 RELDX=17, STPPAR=5) C PARAMETER (ZERO=0.D+0) DATA MODEL1/' ',' ',' ',' ',' G ',' S '/, 1 MODEL2/' G ',' S ','G-S ','S-G ','-S-G','-G-S'/ C C------------------------------- BODY -------------------------------- C PU = IV(PRUNIT) IF (PU .EQ. 0) GO TO 999 IV1 = IV(1) IF (IV1 .GT. 62) IV1 = IV1 - 51 OL = IV(OUTLEV) ALG = MOD(IV(ALGSAV)-1,2) + 1 IF (IV1 .LT. 2 .OR. IV1 .GT. 15) GO TO 370 IF (IV1 .GE. 12) GO TO 120 IF (IV1 .EQ. 2 .AND. IV(NITER) .EQ. 0) GO TO 390 IF (OL .EQ. 0) GO TO 120 IF (IV1 .GE. 10 .AND. IV(PRNTIT) .EQ. 0) GO TO 120 IF (IV1 .GT. 2) GO TO 10 IV(PRNTIT) = IV(PRNTIT) + 1 IF (IV(PRNTIT) .LT. IABS(OL)) GO TO 999 10 NF = IV(NFCALL) - IABS(IV(NFCOV)) IV(PRNTIT) = 0 RELDF = ZERO PRELDF = ZERO OLDF = MAX( ABS(V(F0)), ABS(V(F))) IF (OLDF .LE. ZERO) GO TO 20 RELDF = V(FDIF) / OLDF PRELDF = V(PREDUC) / OLDF 20 IF (OL .GT. 0) GO TO 60 C C *** PRINT SHORT SUMMARY LINE *** C IF (IV(NEEDHD) .EQ. 1 .AND. ALG .EQ. 1) WRITE(PU,30) 30 FORMAT(/10H IT NF,6X,1HF,7X,5HRELDF,3X,6HPRELDF,3X,5HRELDX, 1 2X,13HMODEL STPPAR) IF (IV(NEEDHD) .EQ. 1 .AND. ALG .EQ. 2) WRITE(PU,40) 40 FORMAT(/11H IT NF,7X,1HF,8X,5HRELDF,4X,6HPRELDF,4X,5HRELDX, 1 3X,6HSTPPAR) IV(NEEDHD) = 0 IF (ALG .EQ. 2) GO TO 50 M = IV(SUSED) WRITE(PU,100) IV(NITER), NF, V(F), RELDF, PRELDF, V(RELDX), 1 MODEL1(M), MODEL2(M), V(STPPAR) GO TO 120 C 50 WRITE(PU,110) IV(NITER), NF, V(F), RELDF, PRELDF, V(RELDX), 1 V(STPPAR) GO TO 120 C C *** PRINT LONG SUMMARY LINE *** C 60 IF (IV(NEEDHD) .EQ. 1 .AND. ALG .EQ. 1) WRITE(PU,70) 70 FORMAT(/11H IT NF,6X,1HF,7X,5HRELDF,3X,6HPRELDF,3X,5HRELDX, 1 2X,13HMODEL STPPAR,2X,6HD*STEP,2X,7HNPRELDF) IF (IV(NEEDHD) .EQ. 1 .AND. ALG .EQ. 2) WRITE(PU,80) 80 FORMAT(/11H IT NF,7X,1HF,8X,5HRELDF,4X,6HPRELDF,4X,5HRELDX, 1 3X,6HSTPPAR,3X,6HD*STEP,3X,7HNPRELDF) IV(NEEDHD) = 0 NRELDF = ZERO IF (OLDF .GT. ZERO) NRELDF = V(NREDUC) / OLDF IF (ALG .EQ. 2) GO TO 90 M = IV(SUSED) WRITE(PU,100) IV(NITER), NF, V(F), RELDF, PRELDF, V(RELDX), 1 MODEL1(M), MODEL2(M), V(STPPAR), V(DSTNRM), NRELDF GO TO 120 C 90 WRITE(PU,110) IV(NITER), NF, V(F), RELDF, PRELDF, 1 V(RELDX), V(STPPAR), V(DSTNRM), NRELDF 100 FORMAT(I6,I5,E10.3,2E9.2,E8.1,A3,A4,2E8.1,E9.2) 110 FORMAT(I6,I5,E11.3,2E10.2,3E9.1,E10.2) C 120 IF (IV1 .LE. 2) GO TO 999 I = IV(STATPR) IF (I .EQ. (-1)) GO TO 460 IF (I + IV1 .LT. 0) GO TO 460 GO TO (999, 999, 130, 150, 170, 190, 210, 230, 250, 270, 290, 310, 1 330, 350, 500), IV1 C 130 WRITE(PU,140) 140 FORMAT(/26H ***** X-CONVERGENCE *****) GO TO 430 C 150 WRITE(PU,160) 160 FORMAT(/42H ***** RELATIVE FUNCTION CONVERGENCE *****) GO TO 430 C 170 WRITE(PU,180) 180 FORMAT(/49H ***** X- AND RELATIVE FUNCTION CONVERGENCE *****) GO TO 430 C 190 WRITE(PU,200) 200 FORMAT(/42H ***** ABSOLUTE FUNCTION CONVERGENCE *****) GO TO 430 C 210 WRITE(PU,220) 220 FORMAT(/33H ***** SINGULAR CONVERGENCE *****) GO TO 430 C 230 WRITE(PU,240) 240 FORMAT(/30H ***** FALSE CONVERGENCE *****) GO TO 430 C 250 WRITE(PU,260) 260 FORMAT(/38H ***** FUNCTION EVALUATION LIMIT *****) GO TO 430 C 270 WRITE(PU,280) 280 FORMAT(/28H ***** ITERATION LIMIT *****) GO TO 430 C 290 WRITE(PU,300) 300 FORMAT(/18H ***** STOPX *****) GO TO 430 C 310 WRITE(PU,320) 320 FORMAT(/44H ***** INITIAL F(X) CANNOT BE COMPUTED *****) C GO TO 390 C 330 WRITE(PU,340) 340 FORMAT(/37H ***** BAD PARAMETERS TO ASSESS *****) GO TO 999 C 350 WRITE(PU,360) 360 FORMAT(/43H ***** GRADIENT COULD NOT BE COMPUTED *****) IF (IV(NITER) .GT. 0) GO TO 460 GO TO 390 C 370 WRITE(PU,380) IV(1) 380 FORMAT(/14H ***** IV(1) =,I5,6H *****) GO TO 999 C C *** INITIAL CALL ON DITSUM *** C 390 IF (IV(X0PRT) .NE. 0) WRITE(PU,400) (I, X(I), D(I), I = 1, P) 400 FORMAT(/23H I INITIAL X(I),8X,4HD(I)//(1X,I5,E17.6,E14.3)) C *** THE FOLLOWING ARE TO AVOID UNDEFINED VARIABLES WHEN THE C *** FUNCTION EVALUATION LIMIT IS 1... V(DSTNRM) = ZERO V(FDIF) = ZERO V(NREDUC) = ZERO V(PREDUC) = ZERO V(RELDX) = ZERO IF (IV1 .GE. 12) GO TO 999 IV(NEEDHD) = 0 IV(PRNTIT) = 0 IF (OL .EQ. 0) GO TO 999 IF (OL .LT. 0 .AND. ALG .EQ. 1) WRITE(PU,30) IF (OL .LT. 0 .AND. ALG .EQ. 2) WRITE(PU,40) IF (OL .GT. 0 .AND. ALG .EQ. 1) WRITE(PU,70) IF (OL .GT. 0 .AND. ALG .EQ. 2) WRITE(PU,80) IF (ALG .EQ. 1) WRITE(PU,410) IV(NFCALL), V(F) IF (ALG .EQ. 2) WRITE(PU,420) IV(NFCALL), V(F) 410 FORMAT(/6H 0,I5,E10.3) 420 FORMAT(/6H 0,I5,E11.3) GO TO 999 C C *** PRINT VARIOUS INFORMATION REQUESTED ON SOLUTION *** C 430 IV(NEEDHD) = 1 IF (IV(STATPR) .LE. 0) GO TO 460 OLDF = MAX( ABS(V(F0)), ABS(V(F))) PRELDF = ZERO NRELDF = ZERO IF (OLDF .LE. ZERO) GO TO 440 PRELDF = V(PREDUC) / OLDF NRELDF = V(NREDUC) / OLDF 440 NF = IV(NFCALL) - IV(NFCOV) NG = IV(NGCALL) - IV(NGCOV) WRITE(PU,450) V(F), V(RELDX), NF, NG, PRELDF, NRELDF 450 FORMAT(/9H FUNCTION,E17.6,8H RELDX,E17.3/12H FUNC. EVALS, 1 I8,9X,11HGRAD. EVALS,I8/7H PRELDF,E16.3,6X,7HNPRELDF,E15.3) C 460 IF (IV(SOLPRT) .EQ. 0) GO TO 999 IV(NEEDHD) = 1 IF (IV(ALGSAV) .GT. 2) GO TO 999 WRITE(PU,470) 470 FORMAT(/22H I FINAL X(I),8X,4HD(I),10X,4HG(I)/) DO 480 I = 1, P 480 WRITE(PU,490) I, X(I), D(I), G(I) 490 FORMAT(1X,I5,E16.6,2E14.3) GO TO 999 C 500 WRITE(PU,510) 510 FORMAT(/24H INCONSISTENT DIMENSIONS) 999 RETURN C *** LAST LINE OF DITSUM FOLLOWS *** END SUBROUTINE DIVSET(ALG, IV, LIV, LV, V) C C *** SUPPLY ***SOL (VERSION 2.3) DEFAULT VALUES TO IV AND V *** C C *** ALG = 1 MEANS REGRESSION CONSTANTS. C *** ALG = 2 MEANS GENERAL UNCONSTRAINED OPTIMIZATION CONSTANTS. C INTEGER LIV, LV INTEGER ALG, IV(LIV) DOUBLE PRECISION V(LV) C INTEGER I7MDCN EXTERNAL I7MDCN,DV7DFL C I7MDCN... RETURNS MACHINE-DEPENDENT INTEGER CONSTANTS. C DV7DFL.... PROVIDES DEFAULT VALUES TO V. C INTEGER ALG1, MIV, MV INTEGER MINIV(4), MINV(4) C C *** SUBSCRIPTS FOR IV *** C INTEGER ALGSAV, COVPRT, COVREQ, DRADPR, DTYPE, HC, IERR, INITH, 1 INITS, IPIVOT, IVNEED, LASTIV, LASTV, LMAT, MXFCAL, 2 MXITER, NFCOV, NGCOV, NVDFLT, NVSAVE, OUTLEV, PARPRT, 3 PARSAV, PERM, PRUNIT, QRTYP, RDREQ, RMAT, SOLPRT, STATPR, 4 VNEED, VSAVE, X0PRT C C *** IV SUBSCRIPT VALUES *** C PARAMETER (ALGSAV=51, COVPRT=14, COVREQ=15, DRADPR=101, DTYPE=16, 1 HC=71, IERR=75, INITH=25, INITS=25, IPIVOT=76, 2 IVNEED=3, LASTIV=44, LASTV=45, LMAT=42, MXFCAL=17, 3 MXITER=18, NFCOV=52, NGCOV=53, NVDFLT=50, NVSAVE=9, 4 OUTLEV=19, PARPRT=20, PARSAV=49, PERM=58, PRUNIT=21, 5 QRTYP=80, RDREQ=57, RMAT=78, SOLPRT=22, STATPR=23, 6 VNEED=4, VSAVE=60, X0PRT=24) DATA MINIV(1)/82/, MINIV(2)/59/, MINIV(3)/103/, MINIV(4)/103/, 1 MINV(1)/98/, MINV(2)/71/, MINV(3)/101/, MINV(4)/85/ C C------------------------------- BODY -------------------------------- C IF (PRUNIT .LE. LIV) IV(PRUNIT) = I7MDCN(1) IF (ALGSAV .LE. LIV) IV(ALGSAV) = ALG IF (ALG .LT. 1 .OR. ALG .GT. 4) GO TO 40 MIV = MINIV(ALG) IF (LIV .LT. MIV) GO TO 20 MV = MINV(ALG) IF (LV .LT. MV) GO TO 30 ALG1 = MOD(ALG-1,2) + 1 CALL DV7DFL(ALG1, LV, V) IV(1) = 12 IF (ALG .GT. 2) IV(DRADPR) = 1 IV(IVNEED) = 0 IV(LASTIV) = MIV IV(LASTV) = MV IV(LMAT) = MV + 1 IV(MXFCAL) = 200 IV(MXITER) = 150 IV(OUTLEV) = 1 IV(PARPRT) = 1 IV(PERM) = MIV + 1 IV(SOLPRT) = 1 IV(STATPR) = 1 IV(VNEED) = 0 IV(X0PRT) = 1 C IF (ALG1 .GE. 2) GO TO 10 C C *** REGRESSION VALUES C IV(COVPRT) = 3 IV(COVREQ) = 1 IV(DTYPE) = 1 IV(HC) = 0 IV(IERR) = 0 IV(INITS) = 0 IV(IPIVOT) = 0 IV(NVDFLT) = 32 IV(VSAVE) = 58 IF (ALG .GT. 2) IV(VSAVE) = IV(VSAVE) + 3 IV(PARSAV) = IV(VSAVE) + NVSAVE IV(QRTYP) = 1 IV(RDREQ) = 3 IV(RMAT) = 0 GO TO 999 C C *** GENERAL OPTIMIZATION VALUES C 10 IV(DTYPE) = 0 IV(INITH) = 1 IV(NFCOV) = 0 IV(NGCOV) = 0 IV(NVDFLT) = 25 IV(PARSAV) = 47 IF (ALG .GT. 2) IV(PARSAV) = 61 GO TO 999 C 20 IV(1) = 15 GO TO 999 C 30 IV(1) = 16 GO TO 999 C 40 IV(1) = 67 C 999 RETURN C *** LAST LINE OF DIVSET FOLLOWS *** END SUBROUTINE DL7ITV(N, X, L, Y) C C *** SOLVE (L**T)*X = Y, WHERE L IS AN N X N LOWER TRIANGULAR C *** MATRIX STORED COMPACTLY BY ROWS. X AND Y MAY OCCUPY THE SAME C *** STORAGE. *** C INTEGER N DOUBLE PRECISION X(N), L(1), Y(N) INTEGER I, II, IJ, IM1, I0, J, NP1 DOUBLE PRECISION XI, ZERO PARAMETER (ZERO=0.D+0) C DO 10 I = 1, N 10 X(I) = Y(I) NP1 = N + 1 I0 = N*(N+1)/2 DO 30 II = 1, N I = NP1 - II XI = X(I)/L(I0) X(I) = XI IF (I .LE. 1) GO TO 999 I0 = I0 - I IF (XI .EQ. ZERO) GO TO 30 IM1 = I - 1 DO 20 J = 1, IM1 IJ = I0 + J X(J) = X(J) - XI*L(IJ) 20 CONTINUE 30 CONTINUE 999 RETURN C *** LAST LINE OF DL7ITV FOLLOWS *** END SUBROUTINE DL7IVM(N, X, L, Y) C C *** SOLVE L*X = Y, WHERE L IS AN N X N LOWER TRIANGULAR C *** MATRIX STORED COMPACTLY BY ROWS. X AND Y MAY OCCUPY THE SAME C *** STORAGE. *** C INTEGER N DOUBLE PRECISION X(N), L(1), Y(N) DOUBLE PRECISION DD7TPR EXTERNAL DD7TPR INTEGER I, J, K DOUBLE PRECISION T, ZERO PARAMETER (ZERO=0.D+0) C DO 10 K = 1, N IF (Y(K) .NE. ZERO) GO TO 20 X(K) = ZERO 10 CONTINUE GO TO 999 20 J = K*(K+1)/2 X(K) = Y(K) / L(J) IF (K .GE. N) GO TO 999 K = K + 1 DO 30 I = K, N T = DD7TPR(I-1, L(J+1), X) J = J + I X(I) = (Y(I) - T)/L(J) 30 CONTINUE 999 RETURN C *** LAST LINE OF DL7IVM FOLLOWS *** END SUBROUTINE DL7MST(D, G, IERR, IPIVOT, KA, P, QTR, R, STEP, V, W) C C *** COMPUTE LEVENBERG-MARQUARDT STEP USING MORE-HEBDEN TECHNIQUE ** C *** NL2SOL VERSION 2.2. *** C C *** PARAMETER DECLARATIONS *** C INTEGER IERR, KA, P INTEGER IPIVOT(P) DOUBLE PRECISION D(P), G(P), QTR(P), R(1), STEP(P), V(21), W(1) C DIMENSION W(P*(P+5)/2 + 4) C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** PURPOSE *** C C GIVEN THE R MATRIX FROM THE QR DECOMPOSITION OF A JACOBIAN C MATRIX, J, AS WELL AS Q-TRANSPOSE TIMES THE CORRESPONDING C RESIDUAL VECTOR, RESID, THIS SUBROUTINE COMPUTES A LEVENBERG- C MARQUARDT STEP OF APPROXIMATE LENGTH V(RADIUS) BY THE MORE- C TECHNIQUE. C C *** PARAMETER DESCRIPTION *** C C D (IN) = THE SCALE VECTOR. C G (IN) = THE GRADIENT VECTOR (J**T)*R. C IERR (I/O) = RETURN CODE FROM QRFACT OR DQ7RGS -- 0 MEANS R HAS C FULL RANK. C IPIVOT (I/O) = PERMUTATION ARRAY FROM QRFACT OR DQ7RGS, WHICH COMPUTE C QR DECOMPOSITIONS WITH COLUMN PIVOTING. C KA (I/O). KA .LT. 0 ON INPUT MEANS THIS IS THE FIRST CALL ON C DL7MST FOR THE CURRENT R AND QTR. ON OUTPUT KA CON- C TAINS THE NUMBER OF HEBDEN ITERATIONS NEEDED TO DETERMINE C STEP. KA = 0 MEANS A GAUSS-NEWTON STEP. C P (IN) = NUMBER OF PARAMETERS. C QTR (IN) = (Q**T)*RESID = Q-TRANSPOSE TIMES THE RESIDUAL VECTOR. C R (IN) = THE R MATRIX, STORED COMPACTLY BY COLUMNS. C STEP (OUT) = THE LEVENBERG-MARQUARDT STEP COMPUTED. C V (I/O) CONTAINS VARIOUS CONSTANTS AND VARIABLES DESCRIBED BELOW. C W (I/O) = WORKSPACE OF LENGTH P*(P+5)/2 + 4. C C *** ENTRIES IN V *** C C V(DGNORM) (I/O) = 2-NORM OF (D**-1)*G. C V(DSTNRM) (I/O) = 2-NORM OF D*STEP. C V(DST0) (I/O) = 2-NORM OF GAUSS-NEWTON STEP (FOR NONSING. J). C V(EPSLON) (IN) = MAX. REL. ERROR ALLOWED IN TWONORM(R)**2 MINUS C TWONORM(R - J*STEP)**2. (SEE ALGORITHM NOTES BELOW.) C V(GTSTEP) (OUT) = INNER PRODUCT BETWEEN G AND STEP. C V(NREDUC) (OUT) = HALF THE REDUCTION IN THE SUM OF SQUARES PREDICTED C FOR A GAUSS-NEWTON STEP. C V(PHMNFC) (IN) = TOL. (TOGETHER WITH V(PHMXFC)) FOR ACCEPTING STEP C (MORE*S SIGMA). THE ERROR V(DSTNRM) - V(RADIUS) MUST LIE C BETWEEN V(PHMNFC)*V(RADIUS) AND V(PHMXFC)*V(RADIUS). C V(PHMXFC) (IN) (SEE V(PHMNFC).) C V(PREDUC) (OUT) = HALF THE REDUCTION IN THE SUM OF SQUARES PREDICTED C BY THE STEP RETURNED. C V(RADIUS) (IN) = RADIUS OF CURRENT (SCALED) TRUST REGION. C V(RAD0) (I/O) = VALUE OF V(RADIUS) FROM PREVIOUS CALL. C V(STPPAR) (I/O) = MARQUARDT PARAMETER (OR ITS NEGATIVE IF THE SPECIAL C CASE MENTIONED BELOW IN THE ALGORITHM NOTES OCCURS). C C NOTE -- SEE DATA STATEMENT BELOW FOR VALUES OF ABOVE SUBSCRIPTS. C C *** USAGE NOTES *** C C IF IT IS DESIRED TO RECOMPUTE STEP USING A DIFFERENT VALUE OF C V(RADIUS), THEN THIS ROUTINE MAY BE RESTARTED BY CALLING IT C WITH ALL PARAMETERS UNCHANGED EXCEPT V(RADIUS). (THIS EXPLAINS C WHY MANY PARAMETERS ARE LISTED AS I/O). ON AN INTIIAL CALL (ONE C WITH KA = -1), THE CALLER NEED ONLY HAVE INITIALIZED D, G, KA, P, C QTR, R, V(EPSLON), V(PHMNFC), V(PHMXFC), V(RADIUS), AND V(RAD0). C C *** APPLICATION AND USAGE RESTRICTIONS *** C C THIS ROUTINE IS CALLED AS PART OF THE NL2SOL (NONLINEAR LEAST- C SQUARES) PACKAGE (REF. 1). C C *** ALGORITHM NOTES *** C C THIS CODE IMPLEMENTS THE STEP COMPUTATION SCHEME DESCRIBED IN C REFS. 2 AND 4. FAST GIVENS TRANSFORMATIONS (SEE REF. 3, PP. 60- C 62) ARE USED TO COMPUTE STEP WITH A NONZERO MARQUARDT PARAMETER. C A SPECIAL CASE OCCURS IF J IS (NEARLY) SINGULAR AND V(RADIUS) C IS SUFFICIENTLY LARGE. IN THIS CASE THE STEP RETURNED IS SUCH C THAT TWONORM(R)**2 - TWONORM(R - J*STEP)**2 DIFFERS FROM ITS C OPTIMAL VALUE BY LESS THAN V(EPSLON) TIMES THIS OPTIMAL VALUE, C WHERE J AND R DENOTE THE ORIGINAL JACOBIAN AND RESIDUAL. (SEE C REF. 2 FOR MORE DETAILS.) C C *** FUNCTIONS AND SUBROUTINES CALLED *** C C DD7TPR - RETURNS INNER PRODUCT OF TWO VECTORS. C DL7ITV - APPLY INVERSE-TRANSPOSE OF COMPACT LOWER TRIANG. MATRIX. C DL7IVM - APPLY INVERSE OF COMPACT LOWER TRIANG. MATRIX. C DV7CPY - COPIES ONE VECTOR TO ANOTHER. C DV2NRM - RETURNS 2-NORM OF A VECTOR. C C *** REFERENCES *** C C 1. DENNIS, J.E., GAY, D.M., AND WELSCH, R.E. (1981), AN ADAPTIVE C NONLINEAR LEAST-SQUARES ALGORITHM, ACM TRANS. MATH. C SOFTWARE, VOL. 7, NO. 3. C 2. GAY, D.M. (1981), COMPUTING OPTIMAL LOCALLY CONSTRAINED STEPS, C SIAM J. SCI. STATIST. COMPUTING, VOL. 2, NO. 2, PP. C 186-197. C 3. LAWSON, C.L., AND HANSON, R.J. (1974), SOLVING LEAST SQUARES C PROBLEMS, PRENTICE-HALL, ENGLEWOOD CLIFFS, N.J. C 4. MORE, J.J. (1978), THE LEVENBERG-MARQUARDT ALGORITHM, IMPLEMEN- C TATION AND THEORY, PP.105-116 OF SPRINGER LECTURE NOTES C IN MATHEMATICS NO. 630, EDITED BY G.A. WATSON, SPRINGER- C VERLAG, BERLIN AND NEW YORK. C C *** GENERAL *** C C CODED BY DAVID M. GAY. C THIS SUBROUTINE WAS WRITTEN IN CONNECTION WITH RESEARCH C SUPPORTED BY THE NATIONAL SCIENCE FOUNDATION UNDER GRANTS C MCS-7600324, DCR75-10143, 76-14311DSS, MCS76-11989, AND C MCS-7906671. C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** LOCAL VARIABLES *** C INTEGER DSTSAV, I, IP1, I1, J1, K, KALIM, L, LK0, PHIPIN, 1 PP1O2, RES, RES0, RMAT, RMAT0, UK0 DOUBLE PRECISION A, ADI, ALPHAK, B, DFACSQ, DST, DTOL, D1, D2, 1 LK, OLDPHI, PHI, PHIMAX, PHIMIN, PSIFAC, RAD, 2 SI, SJ, SQRTAK, T, TWOPSI, UK, WL C C *** CONSTANTS *** DOUBLE PRECISION DFAC, EIGHT, HALF, NEGONE, ONE, P001, THREE, 1 TTOL, ZERO DOUBLE PRECISION BIG C C *** EXTERNAL FUNCTIONS AND SUBROUTINES *** C DOUBLE PRECISION DD7TPR, DL7SVN, DR7MDC, DV2NRM EXTERNAL DD7TPR, DL7ITV, DL7IVM, DL7SVN, DR7MDC,DV7CPY, DV2NRM C C *** SUBSCRIPTS FOR V *** C INTEGER DGNORM, DSTNRM, DST0, EPSLON, GTSTEP, NREDUC, PHMNFC, 1 PHMXFC, PREDUC, RADIUS, RAD0, STPPAR PARAMETER (DGNORM=1, DSTNRM=2, DST0=3, EPSLON=19, GTSTEP=4, 1 NREDUC=6, PHMNFC=20, PHMXFC=21, PREDUC=7, RADIUS=8, 2 RAD0=9, STPPAR=5) C PARAMETER (DFAC=256.D+0, EIGHT=8.D+0, HALF=0.5D+0, NEGONE=-1.D+0, 1 ONE=1.D+0, P001=1.D-3, THREE=3.D+0, TTOL=2.5D+0, 2 ZERO=0.D+0) SAVE BIG DATA BIG/0.D+0/ C C *** BODY *** C C *** FOR USE IN RECOMPUTING STEP, THE FINAL VALUES OF LK AND UK, C *** THE INVERSE DERIVATIVE OF MORE*S PHI AT 0 (FOR NONSING. J) C *** AND THE VALUE RETURNED AS V(DSTNRM) ARE STORED AT W(LK0), C *** W(UK0), W(PHIPIN), AND W(DSTSAV) RESPECTIVELY. LK0 = P + 1 PHIPIN = LK0 + 1 UK0 = PHIPIN + 1 DSTSAV = UK0 + 1 RMAT0 = DSTSAV C *** A COPY OF THE R-MATRIX FROM THE QR DECOMPOSITION OF J IS C *** STORED IN W STARTING AT W(RMAT), AND A COPY OF THE RESIDUAL C *** VECTOR IS STORED IN W STARTING AT W(RES). THE LOOPS BELOW C *** THAT UPDATE THE QR DECOMP. FOR A NONZERO MARQUARDT PARAMETER C *** WORK ON THESE COPIES. RMAT = RMAT0 + 1 PP1O2 = P * (P + 1) / 2 RES0 = PP1O2 + RMAT0 RES = RES0 + 1 RAD = V(RADIUS) IF (RAD .GT. ZERO) 1 PSIFAC = V(EPSLON)/((EIGHT*(V(PHMNFC) + ONE) + THREE) * RAD**2) IF (BIG .LE. ZERO) BIG = DR7MDC(6) PHIMAX = V(PHMXFC) * RAD PHIMIN = V(PHMNFC) * RAD C *** DTOL, DFAC, AND DFACSQ ARE USED IN RESCALING THE FAST GIVENS C *** REPRESENTATION OF THE UPDATED QR DECOMPOSITION. DTOL = ONE/DFAC DFACSQ = DFAC*DFAC C *** OLDPHI IS USED TO DETECT LIMITS OF NUMERICAL ACCURACY. IF C *** WE RECOMPUTE STEP AND IT DOES NOT CHANGE, THEN WE ACCEPT IT. OLDPHI = ZERO LK = ZERO UK = ZERO KALIM = KA + 12 C C *** START OR RESTART, DEPENDING ON KA *** C IF (KA) 10, 20, 370 C C *** FRESH START -- COMPUTE V(NREDUC) *** C 10 KA = 0 KALIM = 12 K = P IF (IERR .NE. 0) K = IABS(IERR) - 1 V(NREDUC) = HALF*DD7TPR(K, QTR, QTR) C C *** SET UP TO TRY INITIAL GAUSS-NEWTON STEP *** C 20 V(DST0) = NEGONE IF (IERR .NE. 0) GO TO 90 T = DL7SVN(P, R, STEP, W(RES)) IF (T .GE. ONE) GO TO 30 IF (DV2NRM(P, QTR) .GE. BIG*T) GO TO 90 C C *** COMPUTE GAUSS-NEWTON STEP *** C C *** NOTE -- THE R-MATRIX IS STORED COMPACTLY BY COLUMNS IN C *** R(1), R(2), R(3), ... IT IS THE TRANSPOSE OF A C *** LOWER TRIANGULAR MATRIX STORED COMPACTLY BY ROWS, AND WE C *** TREAT IT AS SUCH WHEN USING DL7ITV AND DL7IVM. 30 CALL DL7ITV(P, W, R, QTR) C *** TEMPORARILY STORE PERMUTED -D*STEP IN STEP. DO 60 I = 1, P J1 = IPIVOT(I) STEP(I) = D(J1)*W(I) 60 CONTINUE DST = DV2NRM(P, STEP) V(DST0) = DST PHI = DST - RAD IF (PHI .LE. PHIMAX) GO TO 410 C *** IF THIS IS A RESTART, GO TO 110 *** IF (KA .GT. 0) GO TO 110 C C *** GAUSS-NEWTON STEP WAS UNACCEPTABLE. COMPUTE L0 *** C DO 70 I = 1, P J1 = IPIVOT(I) STEP(I) = D(J1)*(STEP(I)/DST) 70 CONTINUE CALL DL7IVM(P, STEP, R, STEP) T = ONE / DV2NRM(P, STEP) W(PHIPIN) = (T/RAD)*T LK = PHI*W(PHIPIN) C C *** COMPUTE U0 *** C 90 DO 100 I = 1, P 100 W(I) = G(I)/D(I) V(DGNORM) = DV2NRM(P, W) UK = V(DGNORM)/RAD IF (UK .LE. ZERO) GO TO 390 C C *** ALPHAK WILL BE USED AS THE CURRENT MARQUARDT PARAMETER. WE C *** USE MORE*S SCHEME FOR INITIALIZING IT. C ALPHAK = ABS(V(STPPAR)) * V(RAD0)/RAD ALPHAK = MIN(UK, MAX(ALPHAK, LK)) C C C *** TOP OF LOOP -- INCREMENT KA, COPY R TO RMAT, QTR TO RES *** C 110 KA = KA + 1 CALL DV7CPY(PP1O2, W(RMAT), R) CALL DV7CPY(P, W(RES), QTR) C C *** SAFEGUARD ALPHAK AND INITIALIZE FAST GIVENS SCALE VECTOR. *** C IF (ALPHAK .LE. ZERO .OR. ALPHAK .LT. LK .OR. ALPHAK .GE. UK) 1 ALPHAK = UK * MAX(P001, SQRT(LK/UK)) IF (ALPHAK .LE. ZERO) ALPHAK = HALF * UK SQRTAK = SQRT(ALPHAK) DO 120 I = 1, P 120 W(I) = ONE C C *** ADD ALPHAK*D AND UPDATE QR DECOMP. USING FAST GIVENS TRANS. *** C DO 270 I = 1, P C *** GENERATE, APPLY 1ST GIVENS TRANS. FOR ROW I OF ALPHAK*D. C *** (USE STEP TO STORE TEMPORARY ROW) *** L = I*(I+1)/2 + RMAT0 WL = W(L) D2 = ONE D1 = W(I) J1 = IPIVOT(I) ADI = SQRTAK*D(J1) IF (ADI .GE. ABS(WL)) GO TO 150 130 A = ADI/WL B = D2*A/D1 T = A*B + ONE IF (T .GT. TTOL) GO TO 150 W(I) = D1/T D2 = D2/T W(L) = T*WL A = -A DO 140 J1 = I, P L = L + J1 STEP(J1) = A*W(L) 140 CONTINUE GO TO 170 C 150 B = WL/ADI A = D1*B/D2 T = A*B + ONE IF (T .GT. TTOL) GO TO 130 W(I) = D2/T D2 = D1/T W(L) = T*ADI DO 160 J1 = I, P L = L + J1 WL = W(L) STEP(J1) = -WL W(L) = A*WL 160 CONTINUE C 170 IF (I .EQ. P) GO TO 280 C C *** NOW USE GIVENS TRANS. TO ZERO ELEMENTS OF TEMP. ROW *** C IP1 = I + 1 DO 260 I1 = IP1, P L = I1*(I1+1)/2 + RMAT0 WL = W(L) SI = STEP(I1-1) D1 = W(I1) C C *** RESCALE ROW I1 IF NECESSARY *** C IF (D1 .GE. DTOL) GO TO 190 D1 = D1*DFACSQ WL = WL/DFAC K = L DO 180 J1 = I1, P K = K + J1 W(K) = W(K)/DFAC 180 CONTINUE C C *** USE GIVENS TRANS. TO ZERO NEXT ELEMENT OF TEMP. ROW C 190 IF ( ABS(SI) .GT. ABS(WL)) GO TO 220 IF (SI .EQ. ZERO) GO TO 260 200 A = SI/WL B = D2*A/D1 T = A*B + ONE IF (T .GT. TTOL) GO TO 220 W(L) = T*WL W(I1) = D1/T D2 = D2/T DO 210 J1 = I1, P L = L + J1 WL = W(L) SJ = STEP(J1) W(L) = WL + B*SJ STEP(J1) = SJ - A*WL 210 CONTINUE GO TO 240 C 220 B = WL/SI A = D1*B/D2 T = A*B + ONE IF (T .GT. TTOL) GO TO 200 W(I1) = D2/T D2 = D1/T W(L) = T*SI DO 230 J1 = I1, P L = L + J1 WL = W(L) SJ = STEP(J1) W(L) = A*WL + SJ STEP(J1) = B*SJ - WL 230 CONTINUE C C *** RESCALE TEMP. ROW IF NECESSARY *** C 240 IF (D2 .GE. DTOL) GO TO 260 D2 = D2*DFACSQ DO 250 K = I1, P 250 STEP(K) = STEP(K)/DFAC 260 CONTINUE 270 CONTINUE C C *** COMPUTE STEP *** C 280 CALL DL7ITV(P, W(RES), W(RMAT), W(RES)) C *** RECOVER STEP AND STORE PERMUTED -D*STEP AT W(RES) *** DO 290 I = 1, P J1 = IPIVOT(I) K = RES0 + I T = W(K) STEP(J1) = -T W(K) = T*D(J1) 290 CONTINUE DST = DV2NRM(P, W(RES)) PHI = DST - RAD IF (PHI .LE. PHIMAX .AND. PHI .GE. PHIMIN) GO TO 430 IF (OLDPHI .EQ. PHI) GO TO 430 OLDPHI = PHI C C *** CHECK FOR (AND HANDLE) SPECIAL CASE *** C IF (PHI .GT. ZERO) GO TO 310 IF (KA .GE. KALIM) GO TO 430 TWOPSI = ALPHAK*DST*DST - DD7TPR(P, STEP, G) IF (ALPHAK .GE. TWOPSI*PSIFAC) GO TO 310 V(STPPAR) = -ALPHAK GO TO 440 C C *** UNACCEPTABLE STEP -- UPDATE LK, UK, ALPHAK, AND TRY AGAIN *** C 300 IF (PHI .LT. ZERO) UK = MIN(UK, ALPHAK) GO TO 320 310 IF (PHI .LT. ZERO) UK = ALPHAK 320 DO 330 I = 1, P J1 = IPIVOT(I) K = RES0 + I STEP(I) = D(J1) * (W(K)/DST) 330 CONTINUE CALL DL7IVM(P, STEP, W(RMAT), STEP) DO 340 I = 1, P 340 STEP(I) = STEP(I) / SQRT(W(I)) T = ONE / DV2NRM(P, STEP) ALPHAK = ALPHAK + T*PHI*T/RAD LK = MAX(LK, ALPHAK) ALPHAK = LK GO TO 110 C C *** RESTART *** C 370 LK = W(LK0) UK = W(UK0) IF (V(DST0) .GT. ZERO .AND. V(DST0) - RAD .LE. PHIMAX) GO TO 20 ALPHAK = ABS(V(STPPAR)) DST = W(DSTSAV) PHI = DST - RAD T = V(DGNORM)/RAD IF (RAD .GT. V(RAD0)) GO TO 380 C C *** SMALLER RADIUS *** UK = T IF (ALPHAK .LE. ZERO) LK = ZERO IF (V(DST0) .GT. ZERO) LK = MAX(LK, (V(DST0)-RAD)*W(PHIPIN)) GO TO 300 C C *** BIGGER RADIUS *** 380 IF (ALPHAK .LE. ZERO .OR. UK .GT. T) UK = T LK = ZERO IF (V(DST0) .GT. ZERO) LK = MAX(LK, (V(DST0)-RAD)*W(PHIPIN)) GO TO 300 C C *** SPECIAL CASE -- RAD .LE. 0 OR (G = 0 AND J IS SINGULAR) *** C 390 V(STPPAR) = ZERO DST = ZERO LK = ZERO UK = ZERO V(GTSTEP) = ZERO V(PREDUC) = ZERO DO 400 I = 1, P 400 STEP(I) = ZERO GO TO 450 C C *** ACCEPTABLE GAUSS-NEWTON STEP -- RECOVER STEP FROM W *** C 410 ALPHAK = ZERO DO 420 I = 1, P J1 = IPIVOT(I) STEP(J1) = -W(I) 420 CONTINUE C C *** SAVE VALUES FOR USE IN A POSSIBLE RESTART *** C 430 V(STPPAR) = ALPHAK 440 V(GTSTEP) = MIN(DD7TPR(P,STEP,G), ZERO) V(PREDUC) = HALF * (ALPHAK*DST*DST - V(GTSTEP)) 450 V(DSTNRM) = DST W(DSTSAV) = DST W(LK0) = LK W(UK0) = UK V(RAD0) = RAD C 999 RETURN C C *** LAST LINE OF DL7MST FOLLOWS *** END SUBROUTINE DL7SQR(N, A, L) C C *** COMPUTE A = LOWER TRIANGLE OF L*(L**T), WITH BOTH C *** L AND A STORED COMPACTLY BY ROWS. (BOTH MAY OCCUPY THE C *** SAME STORAGE. C C *** PARAMETERS *** C INTEGER N DOUBLE PRECISION A(1), L(1) C DIMENSION A(N*(N+1)/2), L(N*(N+1)/2) C C *** LOCAL VARIABLES *** C INTEGER I, II, IJ, IK, IP1, I0, J, JJ, JK, J0, K, NP1 DOUBLE PRECISION T C NP1 = N + 1 I0 = N*(N+1)/2 DO 30 II = 1, N I = NP1 - II IP1 = I + 1 I0 = I0 - I J0 = I*(I+1)/2 DO 20 JJ = 1, I J = IP1 - JJ J0 = J0 - J T = 0.0D0 DO 10 K = 1, J IK = I0 + K JK = J0 + K T = T + L(IK)*L(JK) 10 CONTINUE IJ = I0 + J A(IJ) = T 20 CONTINUE 30 CONTINUE 999 RETURN END SUBROUTINE DL7SRT(N1, N, L, A, IRC) C C *** COMPUTE ROWS N1 THROUGH N OF THE CHOLESKY FACTOR L OF C *** A = L*(L**T), WHERE L AND THE LOWER TRIANGLE OF A ARE BOTH C *** STORED COMPACTLY BY ROWS (AND MAY OCCUPY THE SAME STORAGE). C *** IRC = 0 MEANS ALL WENT WELL. IRC = J MEANS THE LEADING C *** PRINCIPAL J X J SUBMATRIX OF A IS NOT POSITIVE DEFINITE -- C *** AND L(J*(J+1)/2) CONTAINS THE (NONPOS.) REDUCED J-TH DIAGONAL. C C *** PARAMETERS *** C INTEGER N1, N, IRC DOUBLE PRECISION L(1), A(1) C DIMENSION L(N*(N+1)/2), A(N*(N+1)/2) C C *** LOCAL VARIABLES *** C INTEGER I, IJ, IK, IM1, I0, J, JK, JM1, J0, K DOUBLE PRECISION T, TD, ZERO C PARAMETER (ZERO=0.D+0) C C *** BODY *** C I0 = N1 * (N1 - 1) / 2 DO 50 I = N1, N TD = ZERO IF (I .EQ. 1) GO TO 40 J0 = 0 IM1 = I - 1 DO 30 J = 1, IM1 T = ZERO IF (J .EQ. 1) GO TO 20 JM1 = J - 1 DO 10 K = 1, JM1 IK = I0 + K JK = J0 + K T = T + L(IK)*L(JK) 10 CONTINUE 20 IJ = I0 + J J0 = J0 + J T = (A(IJ) - T) / L(J0) L(IJ) = T TD = TD + T*T 30 CONTINUE 40 I0 = I0 + I T = A(I0) - TD IF (T .LE. ZERO) GO TO 60 L(I0) = SQRT(T) 50 CONTINUE C IRC = 0 GO TO 999 C 60 L(I0) = T IRC = I C 999 RETURN C C *** LAST LINE OF DL7SRT *** END DOUBLE PRECISION FUNCTION DL7SVN(P, L, X, Y) C C *** ESTIMATE SMALLEST SING. VALUE OF PACKED LOWER TRIANG. MATRIX L C C *** PARAMETER DECLARATIONS *** C INTEGER P DOUBLE PRECISION L(1), X(P), Y(P) C DIMENSION L(P*(P+1)/2) C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** PURPOSE *** C C THIS FUNCTION RETURNS A GOOD OVER-ESTIMATE OF THE SMALLEST C SINGULAR VALUE OF THE PACKED LOWER TRIANGULAR MATRIX L. C C *** PARAMETER DESCRIPTION *** C C P (IN) = THE ORDER OF L. L IS A P X P LOWER TRIANGULAR MATRIX. C L (IN) = ARRAY HOLDING THE ELEMENTS OF L IN ROW ORDER, I.E. C L(1,1), L(2,1), L(2,2), L(3,1), L(3,2), L(3,3), ETC. C X (OUT) IF DL7SVN RETURNS A POSITIVE VALUE, THEN X IS A NORMALIZED C APPROXIMATE LEFT SINGULAR VECTOR CORRESPONDING TO THE C SMALLEST SINGULAR VALUE. THIS APPROXIMATION MAY BE VERY C CRUDE. IF DL7SVN RETURNS ZERO, THEN SOME COMPONENTS OF X C ARE ZERO AND THE REST RETAIN THEIR INPUT VALUES. C Y (OUT) IF DL7SVN RETURNS A POSITIVE VALUE, THEN Y = (L**-1)*X IS AN C UNNORMALIZED APPROXIMATE RIGHT SINGULAR VECTOR CORRESPOND- C ING TO THE SMALLEST SINGULAR VALUE. THIS APPROXIMATION C MAY BE CRUDE. IF DL7SVN RETURNS ZERO, THEN Y RETAINS ITS C INPUT VALUE. THE CALLER MAY PASS THE SAME VECTOR FOR X C AND Y (NONSTANDARD FORTRAN USAGE), IN WHICH CASE Y OVER- C WRITES X (FOR NONZERO DL7SVN RETURNS). C C *** ALGORITHM NOTES *** C C THE ALGORITHM IS BASED ON (1), WITH THE ADDITIONAL PROVISION THAT C DL7SVN = 0 IS RETURNED IF THE SMALLEST DIAGONAL ELEMENT OF L C (IN MAGNITUDE) IS NOT MORE THAN THE UNIT ROUNDOFF TIMES THE C LARGEST. THE ALGORITHM USES A RANDOM NUMBER GENERATOR PROPOSED C IN (4), WHICH PASSES THE SPECTRAL TEST WITH FLYING COLORS -- SEE C (2) AND (3). C C *** SUBROUTINES AND FUNCTIONS CALLED *** C C DV2NRM - FUNCTION, RETURNS THE 2-NORM OF A VECTOR. C C *** REFERENCES *** C C (1) CLINE, A., MOLER, C., STEWART, G., AND WILKINSON, J.H.(1977), C AN ESTIMATE FOR THE CONDITION NUMBER OF A MATRIX, REPORT C TM-310, APPLIED MATH. DIV., ARGONNE NATIONAL LABORATORY. C C (2) HOAGLIN, D.C. (1976), THEORETICAL PROPERTIES OF CONGRUENTIAL C RANDOM-NUMBER GENERATORS -- AN EMPIRICAL VIEW, C MEMORANDUM NS-340, DEPT. OF STATISTICS, HARVARD UNIV. C C (3) KNUTH, D.E. (1969), THE ART OF COMPUTER PROGRAMMING, VOL. 2 C (SEMINUMERICAL ALGORITHMS), ADDISON-WESLEY, READING, MASS. C C (4) SMITH, C.S. (1971), MULTIPLICATIVE PSEUDO-RANDOM NUMBER C GENERATORS WITH PRIME MODULUS, J. ASSOC. COMPUT. MACH. 18, C PP. 586-593. C C *** HISTORY *** C C DESIGNED AND CODED BY DAVID M. GAY (WINTER 1977/SUMMER 1978). C C *** GENERAL *** C C THIS SUBROUTINE WAS WRITTEN IN CONNECTION WITH RESEARCH C SUPPORTED BY THE NATIONAL SCIENCE FOUNDATION UNDER GRANTS C MCS-7600324, DCR75-10143, 76-14311DSS, AND MCS76-11989. C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** LOCAL VARIABLES *** C INTEGER I, II, IX, J, JI, JJ, JJJ, JM1, J0, PM1 DOUBLE PRECISION B, SMINUS, SPLUS, T, XMINUS, XPLUS C C *** CONSTANTS *** C DOUBLE PRECISION HALF, ONE, R9973, ZERO C C *** EXTERNAL FUNCTIONS AND SUBROUTINES *** C DOUBLE PRECISION DD7TPR, DV2NRM EXTERNAL DD7TPR, DV2NRM,DV2AXY C PARAMETER (HALF=0.5D+0, ONE=1.D+0, R9973=9973.D+0, ZERO=0.D+0) C C *** BODY *** C IX = 2 PM1 = P - 1 C C *** FIRST CHECK WHETHER TO RETURN DL7SVN = 0 AND INITIALIZE X *** C II = 0 J0 = P*PM1/2 JJ = J0 + P IF (L(JJ) .EQ. ZERO) GO TO 110 IX = MOD(3432*IX, 9973) B = HALF*(ONE + FLOAT(IX)/R9973) XPLUS = B / L(JJ) X(P) = XPLUS IF (P .LE. 1) GO TO 60 DO 10 I = 1, PM1 II = II + I IF (L(II) .EQ. ZERO) GO TO 110 JI = J0 + I X(I) = XPLUS * L(JI) 10 CONTINUE C C *** SOLVE (L**T)*X = B, WHERE THE COMPONENTS OF B HAVE RANDOMLY C *** CHOSEN MAGNITUDES IN (.5,1) WITH SIGNS CHOSEN TO MAKE X LARGE. C C DO J = P-1 TO 1 BY -1... DO 50 JJJ = 1, PM1 J = P - JJJ C *** DETERMINE X(J) IN THIS ITERATION. NOTE FOR I = 1,2,...,J C *** THAT X(I) HOLDS THE CURRENT PARTIAL SUM FOR ROW I. IX = MOD(3432*IX, 9973) B = HALF*(ONE + FLOAT(IX)/R9973) XPLUS = (B - X(J)) XMINUS = (-B - X(J)) SPLUS = ABS(XPLUS) SMINUS = ABS(XMINUS) JM1 = J - 1 J0 = J*JM1/2 JJ = J0 + J XPLUS = XPLUS/L(JJ) XMINUS = XMINUS/L(JJ) IF (JM1 .EQ. 0) GO TO 30 DO 20 I = 1, JM1 JI = J0 + I SPLUS = SPLUS + ABS(X(I) + L(JI)*XPLUS) SMINUS = SMINUS + ABS(X(I) + L(JI)*XMINUS) 20 CONTINUE 30 IF (SMINUS .GT. SPLUS) XPLUS = XMINUS X(J) = XPLUS C *** UPDATE PARTIAL SUMS *** IF (JM1 .GT. 0) CALL DV2AXY(JM1, X, XPLUS, L(J0+1), X) 50 CONTINUE C C *** NORMALIZE X *** C 60 T = ONE/DV2NRM(P, X) DO 70 I = 1, P 70 X(I) = T*X(I) C C *** SOLVE L*Y = X AND RETURN DL7SVN = 1/TWONORM(Y) *** C DO 100 J = 1, P JM1 = J - 1 J0 = J*JM1/2 JJ = J0 + J T = ZERO IF (JM1 .GT. 0) T = DD7TPR(JM1, L(J0+1), Y) Y(J) = (X(J) - T) / L(JJ) 100 CONTINUE C DL7SVN = ONE/DV2NRM(P, Y) GO TO 999 C 110 DL7SVN = ZERO 999 RETURN C *** LAST LINE OF DL7SVN FOLLOWS *** END DOUBLE PRECISION FUNCTION DL7SVX(P, L, X, Y) C C *** ESTIMATE LARGEST SING. VALUE OF PACKED LOWER TRIANG. MATRIX L C C *** PARAMETER DECLARATIONS *** C INTEGER P DOUBLE PRECISION L(1), X(P), Y(P) C DIMENSION L(P*(P+1)/2) C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** PURPOSE *** C C THIS FUNCTION RETURNS A GOOD UNDER-ESTIMATE OF THE LARGEST C SINGULAR VALUE OF THE PACKED LOWER TRIANGULAR MATRIX L. C C *** PARAMETER DESCRIPTION *** C C P (IN) = THE ORDER OF L. L IS A P X P LOWER TRIANGULAR MATRIX. C L (IN) = ARRAY HOLDING THE ELEMENTS OF L IN ROW ORDER, I.E. C L(1,1), L(2,1), L(2,2), L(3,1), L(3,2), L(3,3), ETC. C X (OUT) IF DL7SVX RETURNS A POSITIVE VALUE, THEN X = (L**T)*Y IS AN C (UNNORMALIZED) APPROXIMATE RIGHT SINGULAR VECTOR C CORRESPONDING TO THE LARGEST SINGULAR VALUE. THIS C APPROXIMATION MAY BE CRUDE. C Y (OUT) IF DL7SVX RETURNS A POSITIVE VALUE, THEN Y = L*X IS A C NORMALIZED APPROXIMATE LEFT SINGULAR VECTOR CORRESPOND- C ING TO THE LARGEST SINGULAR VALUE. THIS APPROXIMATION C MAY BE VERY CRUDE. THE CALLER MAY PASS THE SAME VECTOR C FOR X AND Y (NONSTANDARD FORTRAN USAGE), IN WHICH CASE X C OVER-WRITES Y. C C *** ALGORITHM NOTES *** C C THE ALGORITHM IS BASED ON ANALOGY WITH (1). IT USES A C RANDOM NUMBER GENERATOR PROPOSED IN (4), WHICH PASSES THE C SPECTRAL TEST WITH FLYING COLORS -- SEE (2) AND (3). C C *** SUBROUTINES AND FUNCTIONS CALLED *** C C DV2NRM - FUNCTION, RETURNS THE 2-NORM OF A VECTOR. C C *** REFERENCES *** C C (1) CLINE, A., MOLER, C., STEWART, G., AND WILKINSON, J.H.(1977), C AN ESTIMATE FOR THE CONDITION NUMBER OF A MATRIX, REPORT C TM-310, APPLIED MATH. DIV., ARGONNE NATIONAL LABORATORY. C C (2) HOAGLIN, D.C. (1976), THEORETICAL PROPERTIES OF CONGRUENTIAL C RANDOM-NUMBER GENERATORS -- AN EMPIRICAL VIEW, C MEMORANDUM NS-340, DEPT. OF STATISTICS, HARVARD UNIV. C C (3) KNUTH, D.E. (1969), THE ART OF COMPUTER PROGRAMMING, VOL. 2 C (SEMINUMERICAL ALGORITHMS), ADDISON-WESLEY, READING, MASS. C C (4) SMITH, C.S. (1971), MULTIPLICATIVE PSEUDO-RANDOM NUMBER C GENERATORS WITH PRIME MODULUS, J. ASSOC. COMPUT. MACH. 18, C PP. 586-593. C C *** HISTORY *** C C DESIGNED AND CODED BY DAVID M. GAY (WINTER 1977/SUMMER 1978). C C *** GENERAL *** C C THIS SUBROUTINE WAS WRITTEN IN CONNECTION WITH RESEARCH C SUPPORTED BY THE NATIONAL SCIENCE FOUNDATION UNDER GRANTS C MCS-7600324, DCR75-10143, 76-14311DSS, AND MCS76-11989. C C+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ C C *** LOCAL VARIABLES *** C INTEGER I, IX, J, JI, JJ, JJJ, JM1, J0, PM1, PPLUS1 DOUBLE PRECISION B, BLJI, SMINUS, SPLUS, T, YI C C *** CONSTANTS *** C DOUBLE PRECISION HALF, ONE, R9973, ZERO C C *** EXTERNAL FUNCTIONS AND SUBROUTINES *** C DOUBLE PRECISION DD7TPR, DV2NRM EXTERNAL DD7TPR, DV2NRM,DV2AXY C PARAMETER (HALF=0.5D+0, ONE=1.D+0, R9973=9973.D+0, ZERO=0.D+0) C C *** BODY *** C IX = 2 PPLUS1 = P + 1 PM1 = P - 1 C C *** FIRST INITIALIZE X TO PARTIAL SUMS *** C J0 = P*PM1/2 JJ = J0 + P IX = MOD(3432*IX, 9973) B = HALF*(ONE + FLOAT(IX)/R9973) X(P) = B * L(JJ) IF (P .LE. 1) GO TO 40 DO 10 I = 1, PM1 JI = J0 + I X(I) = B * L(JI) 10 CONTINUE C C *** COMPUTE X = (L**T)*B, WHERE THE COMPONENTS OF B HAVE RANDOMLY C *** CHOSEN MAGNITUDES IN (.5,1) WITH SIGNS CHOSEN TO MAKE X LARGE. C C DO J = P-1 TO 1 BY -1... DO 30 JJJ = 1, PM1 J = P - JJJ C *** DETERMINE X(J) IN THIS ITERATION. NOTE FOR I = 1,2,...,J C *** THAT X(I) HOLDS THE CURRENT PARTIAL SUM FOR ROW I. IX = MOD(3432*IX, 9973) B = HALF*(ONE + FLOAT(IX)/R9973) JM1 = J - 1 J0 = J*JM1/2 SPLUS = ZERO SMINUS = ZERO DO 20 I = 1, J JI = J0 + I BLJI = B * L(JI) SPLUS = SPLUS + ABS(BLJI + X(I)) SMINUS = SMINUS + ABS(BLJI - X(I)) 20 CONTINUE IF (SMINUS .GT. SPLUS) B = -B X(J) = ZERO C *** UPDATE PARTIAL SUMS *** CALL DV2AXY(J, X, B, L(J0+1), X) 30 CONTINUE C C *** NORMALIZE X *** C 40 T = DV2NRM(P, X) IF (T .LE. ZERO) GO TO 80 T = ONE / T DO 50 I = 1, P 50 X(I) = T*X(I) C C *** COMPUTE L*X = Y AND RETURN SVMAX = TWONORM(Y) *** C DO 60 JJJ = 1, P J = PPLUS1 - JJJ JI = J*(J-1)/2 + 1 Y(J) = DD7TPR(J, L(JI), X) 60 CONTINUE C C *** NORMALIZE Y AND SET X = (L**T)*Y *** C T = ONE / DV2NRM(P, Y) JI = 1 DO 70 I = 1, P YI = T * Y(I) X(I) = ZERO CALL DV2AXY(I, X, YI, L(JI), X) JI = JI + I 70 CONTINUE DL7SVX = DV2NRM(P, X) GO TO 999 C 80 DL7SVX = ZERO C 999 RETURN C *** LAST LINE OF DL7SVX FOLLOWS *** END SUBROUTINE DL7TVM(N, X, L, Y) C C *** COMPUTE X = (L**T)*Y, WHERE L IS AN N X N LOWER C *** TRIANGULAR MATRIX STORED COMPACTLY BY ROWS. X AND Y MAY C *** OCCUPY THE SAME STORAGE. *** C INTEGER N DOUBLE PRECISION X(N), L(1), Y(N) C DIMENSION L(N*(N+1)/2) INTEGER I, IJ, I0, J DOUBLE PRECISION YI, ZERO PARAMETER (ZERO=0.D+0) C I0 = 0 DO 20 I = 1, N YI = Y(I) X(I) = ZERO DO 10 J = 1, I IJ = I0 + J X(J) = X(J) + YI*L(IJ) 10 CONTINUE I0 = I0 + I 20 CONTINUE 999 RETURN C *** LAST LINE OF DL7TVM FOLLOWS *** END SUBROUTINE DL7VML(N, X, L, Y) C C *** COMPUTE X = L*Y, WHERE L IS AN N X N LOWER TRIANGULAR C *** MATRIX STORED COMPACTLY BY ROWS. X AND Y MAY OCCUPY THE SAME C *** STORAGE. *** C INTEGER N DOUBLE PRECISION X(N), L(1), Y(N) C DIMENSION L(N*(N+1)/2) INTEGER I, II, IJ, I0, J, NP1 DOUBLE PRECISION T, ZERO PARAMETER (ZERO=0.D+0) C NP1 = N + 1 I0 = N*(N+1)/2 DO 20 II = 1, N I = NP1 - II I0 = I0 - I T = ZERO DO 10 J = 1, I IJ = I0 + J T = T + L(IJ)*Y(J) 10 CONTINUE X(I) = T 20 CONTINUE 999 RETURN C *** LAST LINE OF DL7VML FOLLOWS *** END SUBROUTINE DO7PRD(L, LS, P, S, W, Y, Z) C C *** FOR I = 1..L, SET S = S + W(I)*Y(.,I)*(Z(.,I)**T), I.E., C *** ADD W(I) TIMES THE OUTER PRODUCT OF Y(.,I) AND Z(.,I). C INTEGER L, LS, P DOUBLE PRECISION S(LS), W(L), Y(P,L), Z(P,L) C DIMENSION S(P*(P+1)/2) C INTEGER I, J, K, M DOUBLE PRECISION WK, YI, ZERO DATA ZERO/0.D+0/ C DO 30 K = 1, L WK = W(K) IF (WK .EQ. ZERO) GO TO 30 M = 1 DO 20 I = 1, P YI = WK * Y(I,K) DO 10 J = 1, I S(M) = S(M) + YI*Z(J,K) M = M + 1 10 CONTINUE 20 CONTINUE 30 CONTINUE C 999 RETURN C *** LAST LINE OF DO7PRD FOLLOWS *** END SUBROUTINE DPARCK(ALG, D, IV, LIV, LV, N, V) C C *** CHECK ***SOL (VERSION 2.3) PARAMETERS, PRINT CHANGED VALUES *** C C *** ALG = 1 FOR REGRESSION, ALG = 2 FOR GENERAL UNCONSTRAINED OPT. C INTEGER ALG, LIV, LV, N INTEGER IV(LIV) DOUBLE PRECISION D(N), V(LV) C DOUBLE PRECISION DR7MDC EXTERNAL DIVSET, DR7MDC,DV7CPY,DV7DFL C DIVSET -- SUPPLIES DEFAULT VALUES TO BOTH IV AND V. C DR7MDC -- RETURNS MACHINE-DEPENDENT CONSTANTS. C DV7CPY -- COPIES ONE VECTOR TO ANOTHER. C DV7DFL -- SUPPLIES DEFAULT PARAMETER VALUES TO V ALONE. C C *** LOCAL VARIABLES *** C INTEGER ALG1, I, II, IV1, J, K, L, M, MIV1, MIV2, NDFALT, PARSV1, 1 PU INTEGER IJMP, JLIM(4), MINIV(4), NDFLT(4) CHARACTER*1 VARNM(2), SH(2) CHARACTER*4 CNGD(3), DFLT(3), VN(2,34), WHICH(3) DOUBLE PRECISION BIG, MACHEP, TINY, VK, VM(34), VX(34), ZERO C C *** IV AND V SUBSCRIPTS *** C INTEGER ALGSAV, DINIT, DTYPE, DTYPE0, EPSLON, INITS, IVNEED, 1 LASTIV, LASTV, LMAT, NEXTIV, NEXTV, NVDFLT, OLDN, 2 PARPRT, PARSAV, PERM, PRUNIT, VNEED C C PARAMETER (ALGSAV=51, DINIT=38, DTYPE=16, DTYPE0=54, EPSLON=19, 1 INITS=25, IVNEED=3, LASTIV=44, LASTV=45, LMAT=42, 2 NEXTIV=46, NEXTV=47, NVDFLT=50, OLDN=38, PARPRT=20, 3 PARSAV=49, PERM=58, PRUNIT=21, VNEED=4) SAVE BIG, MACHEP, TINY C DATA BIG/0.D+0/, MACHEP/-1.D+0/, TINY/1.D+0/, ZERO/0.D+0/ DATA VN(1,1),VN(2,1)/'EPSL','ON..'/ DATA VN(1,2),VN(2,2)/'PHMN','FC..'/ DATA VN(1,3),VN(2,3)/'PHMX','FC..'/ DATA VN(1,4),VN(2,4)/'DECF','AC..'/ DATA VN(1,5),VN(2,5)/'INCF','AC..'/ DATA VN(1,6),VN(2,6)/'RDFC','MN..'/ DATA VN(1,7),VN(2,7)/'RDFC','MX..'/ DATA VN(1,8),VN(2,8)/'TUNE','R1..'/ DATA VN(1,9),VN(2,9)/'TUNE','R2..'/ DATA VN(1,10),VN(2,10)/'TUNE','R3..'/ DATA VN(1,11),VN(2,11)/'TUNE','R4..'/ DATA VN(1,12),VN(2,12)/'TUNE','R5..'/ DATA VN(1,13),VN(2,13)/'AFCT','OL..'/ DATA VN(1,14),VN(2,14)/'RFCT','OL..'/ DATA VN(1,15),VN(2,15)/'XCTO','L...'/ DATA VN(1,16),VN(2,16)/'XFTO','L...'/ DATA VN(1,17),VN(2,17)/'LMAX','0...'/ DATA VN(1,18),VN(2,18)/'LMAX','S...'/ DATA VN(1,19),VN(2,19)/'SCTO','L...'/ DATA VN(1,20),VN(2,20)/'DINI','T...'/ DATA VN(1,21),VN(2,21)/'DTIN','IT..'/ DATA VN(1,22),VN(2,22)/'D0IN','IT..'/ DATA VN(1,23),VN(2,23)/'DFAC','....'/ DATA VN(1,24),VN(2,24)/'DLTF','DC..'/ DATA VN(1,25),VN(2,25)/'DLTF','DJ..'/ DATA VN(1,26),VN(2,26)/'DELT','A0..'/ DATA VN(1,27),VN(2,27)/'FUZZ','....'/ DATA VN(1,28),VN(2,28)/'RLIM','IT..'/ DATA VN(1,29),VN(2,29)/'COSM','IN..'/ DATA VN(1,30),VN(2,30)/'HUBE','RC..'/ DATA VN(1,31),VN(2,31)/'RSPT','OL..'/ DATA VN(1,32),VN(2,32)/'SIGM','IN..'/ DATA VN(1,33),VN(2,33)/'ETA0','....'/ DATA VN(1,34),VN(2,34)/'BIAS','....'/ C DATA VM(1)/1.0D-3/, VM(2)/-0.99D+0/, VM(3)/1.0D-3/, VM(4)/1.0D-2/, 1 VM(5)/1.2D+0/, VM(6)/1.D-2/, VM(7)/1.2D+0/, VM(8)/0.D+0/, 2 VM(9)/0.D+0/, VM(10)/1.D-3/, VM(11)/-1.D+0/, VM(13)/0.D+0/, 3 VM(15)/0.D+0/, VM(16)/0.D+0/, VM(19)/0.D+0/, VM(20)/-10.D+0/, 4 VM(21)/0.D+0/, VM(22)/0.D+0/, VM(23)/0.D+0/, VM(27)/1.01D+0/, 5 VM(28)/1.D+10/, VM(30)/0.D+0/, VM(31)/0.D+0/, VM(32)/0.D+0/, 6 VM(34)/0.D+0/ DATA VX(1)/0.9D+0/, VX(2)/-1.D-3/, VX(3)/1.D+1/, VX(4)/0.8D+0/, 1 VX(5)/1.D+2/, VX(6)/0.8D+0/, VX(7)/1.D+2/, VX(8)/0.5D+0/, 2 VX(9)/0.5D+0/, VX(10)/1.D+0/, VX(11)/1.D+0/, VX(14)/0.1D+0/, 3 VX(15)/1.D+0/, VX(16)/1.D+0/, VX(19)/1.D+0/, VX(23)/1.D+0/, 4 VX(24)/1.D+0/, VX(25)/1.D+0/, VX(26)/1.D+0/, VX(27)/1.D+10/, 5 VX(29)/1.D+0/, VX(31)/1.D+0/, VX(32)/1.D+0/, VX(33)/1.D+0/, 6 VX(34)/1.D+0/ C DATA VARNM(1)/'P'/, VARNM(2)/'P'/, SH(1)/'S'/, SH(2)/'H'/ DATA CNGD(1),CNGD(2),CNGD(3)/'---C','HANG','ED V'/, 1 DFLT(1),DFLT(2),DFLT(3)/'NOND','EFAU','LT V'/ DATA IJMP/33/, JLIM(1)/0/, JLIM(2)/24/, JLIM(3)/0/, JLIM(4)/24/, 1 NDFLT(1)/32/, NDFLT(2)/25/, NDFLT(3)/32/, NDFLT(4)/25/ DATA MINIV(1)/82/, MINIV(2)/59/, MINIV(3)/103/, MINIV(4)/103/ C C............................... BODY ................................ C PU = 0 IF (PRUNIT .LE. LIV) PU = IV(PRUNIT) IF (ALGSAV .GT. LIV) GO TO 20 IF (ALG .EQ. IV(ALGSAV)) GO TO 20 IF (PU .NE. 0) WRITE(PU,10) ALG, IV(ALGSAV) 10 FORMAT(/40H THE FIRST PARAMETER TO DIVSET SHOULD BE,I3, 1 12H RATHER THAN,I3) IV(1) = 67 GO TO 999 20 IF (ALG .LT. 1 .OR. ALG .GT. 4) GO TO 340 MIV1 = MINIV(ALG) IF (IV(1) .EQ. 15) GO TO 360 ALG1 = MOD(ALG-1,2) + 1 IF (IV(1) .EQ. 0) CALL DIVSET(ALG, IV, LIV, LV, V) IV1 = IV(1) IF (IV1 .NE. 13 .AND. IV1 .NE. 12) GO TO 30 IF (PERM .LE. LIV) MIV1 = MAX0(MIV1, IV(PERM) - 1) IF (IVNEED .LE. LIV) MIV2 = MIV1 + MAX0(IV(IVNEED), 0) IF (LASTIV .LE. LIV) IV(LASTIV) = MIV2 IF (LIV .LT. MIV1) GO TO 300 IV(IVNEED) = 0 IV(LASTV) = MAX0(IV(VNEED), 0) + IV(LMAT) - 1 IV(VNEED) = 0 IF (LIV .LT. MIV2) GO TO 300 IF (LV .LT. IV(LASTV)) GO TO 320 30 IF (IV1 .LT. 12 .OR. IV1 .GT. 14) GO TO 60 IF (N .GE. 1) GO TO 50 IV(1) = 81 IF (PU .EQ. 0) GO TO 999 WRITE(PU,40) VARNM(ALG1), N 40 FORMAT(/8H /// BAD,A1,2H =,I5) GO TO 999 50 IF (IV1 .NE. 14) IV(NEXTIV) = IV(PERM) IF (IV1 .NE. 14) IV(NEXTV) = IV(LMAT) IF (IV1 .EQ. 13) GO TO 999 K = IV(PARSAV) - EPSLON CALL DV7DFL(ALG1, LV-K, V(K+1)) IV(DTYPE0) = 2 - ALG1 IV(OLDN) = N WHICH(1) = DFLT(1) WHICH(2) = DFLT(2) WHICH(3) = DFLT(3) GO TO 110 60 IF (N .EQ. IV(OLDN)) GO TO 80 IV(1) = 17 IF (PU .EQ. 0) GO TO 999 WRITE(PU,70) VARNM(ALG1), IV(OLDN), N 70 FORMAT(/5H /// ,1A1,14H CHANGED FROM ,I5,4H TO ,I5) GO TO 999 C 80 IF (IV1 .LE. 11 .AND. IV1 .GE. 1) GO TO 100 IV(1) = 80 IF (PU .NE. 0) WRITE(PU,90) IV1 90 FORMAT(/13H /// IV(1) =,I5,28H SHOULD BE BETWEEN 0 AND 14.) GO TO 999 C 100 WHICH(1) = CNGD(1) WHICH(2) = CNGD(2) WHICH(3) = CNGD(3) C 110 IF (IV1 .EQ. 14) IV1 = 12 IF (BIG .GT. TINY) GO TO 120 TINY = DR7MDC(1) MACHEP = DR7MDC(3) BIG = DR7MDC(6) VM(12) = MACHEP VX(12) = BIG VX(13) = BIG VM(14) = MACHEP VM(17) = TINY VX(17) = BIG VM(18) = TINY VX(18) = BIG VX(20) = BIG VX(21) = BIG VX(22) = BIG VM(24) = MACHEP VM(25) = MACHEP VM(26) = MACHEP VX(28) = DR7MDC(5) VM(29) = MACHEP VX(30) = BIG VM(33) = MACHEP 120 M = 0 I = 1 J = JLIM(ALG1) K = EPSLON NDFALT = NDFLT(ALG1) DO 150 L = 1, NDFALT VK = V(K) IF (VK .GE. VM(I) .AND. VK .LE. VX(I)) GO TO 140 M = K IF (PU .NE. 0) WRITE(PU,130) VN(1,I), VN(2,I), K, VK, 1 VM(I), VX(I) 130 FORMAT(/6H /// ,2A4,5H.. V(,I2,3H) =,E11.3,7H SHOULD, 1 11H BE BETWEEN,E11.3,4H AND,E11.3) 140 K = K + 1 I = I + 1 IF (I .EQ. J) I = IJMP 150 CONTINUE C IF (IV(NVDFLT) .EQ. NDFALT) GO TO 170 IV(1) = 51 IF (PU .EQ. 0) GO TO 999 WRITE(PU,160) IV(NVDFLT), NDFALT 160 FORMAT(/13H IV(NVDFLT) =,I5,13H RATHER THAN ,I5) GO TO 999 170 IF ((IV(DTYPE) .GT. 0 .OR. V(DINIT) .GT. ZERO) .AND. IV1 .EQ. 12) 1 GO TO 200 DO 190 I = 1, N IF (D(I) .GT. ZERO) GO TO 190 M = 18 IF (PU .NE. 0) WRITE(PU,180) I, D(I) 180 FORMAT(/8H /// D(,I3,3H) =,E11.3,19H SHOULD BE POSITIVE) 190 CONTINUE 200 IF (M .EQ. 0) GO TO 210 IV(1) = M GO TO 999 C 210 IF (PU .EQ. 0 .OR. IV(PARPRT) .EQ. 0) GO TO 999 IF (IV1 .NE. 12 .OR. IV(INITS) .EQ. ALG1-1) GO TO 230 M = 1 WRITE(PU,220) SH(ALG1), IV(INITS) 220 FORMAT(/22H NONDEFAULT VALUES..../5H INIT,A1,14H..... IV(25) =, 1 I3) 230 IF (IV(DTYPE) .EQ. IV(DTYPE0)) GO TO 250 IF (M .EQ. 0) WRITE(PU,260) WHICH M = 1 WRITE(PU,240) IV(DTYPE) 240 FORMAT(20H DTYPE..... IV(16) =,I3) 250 I = 1 J = JLIM(ALG1) K = EPSLON L = IV(PARSAV) NDFALT = NDFLT(ALG1) DO 290 II = 1, NDFALT IF (V(K) .EQ. V(L)) GO TO 280 IF (M .EQ. 0) WRITE(PU,260) WHICH 260 FORMAT(/1H ,3A4,9HALUES..../) M = 1 WRITE(PU,270) VN(1,I), VN(2,I), K, V(K) 270 FORMAT(1X,2A4,5H.. V(,I2,3H) =,E15.7) 280 K = K + 1 L = L + 1 I = I + 1 IF (I .EQ. J) I = IJMP 290 CONTINUE C IV(DTYPE0) = IV(DTYPE) PARSV1 = IV(PARSAV) CALL DV7CPY(IV(NVDFLT), V(PARSV1), V(EPSLON)) GO TO 999 C 300 IV(1) = 15 IF (PU .EQ. 0) GO TO 999 WRITE(PU,310) LIV, MIV2 310 FORMAT(/10H /// LIV =,I5,17H MUST BE AT LEAST,I5) IF (LIV .LT. MIV1) GO TO 999 IF (LV .LT. IV(LASTV)) GO TO 320 GO TO 999 C 320 IV(1) = 16 IF (PU .NE. 0) WRITE(PU,330) LV, IV(LASTV) 330 FORMAT(/9H /// LV =,I5,17H MUST BE AT LEAST,I5) GO TO 999 C 340 IV(1) = 67 IF (PU .NE. 0) WRITE(PU,350) ALG 350 FORMAT(/10H /// ALG =,I5,21H MUST BE 1 2, 3, OR 4) GO TO 999 360 IF (PU .NE. 0) WRITE(PU,370) LIV, MIV1 370 FORMAT(/10H /// LIV =,I5,17H MUST BE AT LEAST,I5, 1 37H TO COMPUTE TRUE MIN. LIV AND MIN. LV) IF (LASTIV .LE. LIV) IV(LASTIV) = MIV1 IF (LASTV .LE. LIV) IV(LASTV) = 0 C 999 RETURN C *** LAST LINE OF DPARCK FOLLOWS *** END SUBROUTINE DQ7ADR(P, QTR, RMAT, W, Y) C C *** ADD ROW W TO QR FACTORIZATION WITH R MATRIX RMAT AND C *** Q**T * RESIDUAL = QTR. Y = NEW COMPONENT OF RESIDUAL C *** CORRESPONDING TO W. C INTEGER P DOUBLE PRECISION QTR(P), RMAT(1), W(P), Y C DIMENSION RMAT(P*(P+1)/2) C C *** LOCAL VARIABLES *** C INTEGER I, II, IJ, IP1, J DOUBLE PRECISION RI, RW, T, U1, U2, V, WI, WR C DOUBLE PRECISION ONE, ZERO PARAMETER (ONE=1.D+0, ZERO=0.D+0) C C------------------------------ BODY ----------------------------------- C II = 0 DO 60 I = 1, P II = II+I WI = W(I) IF (WI .EQ. ZERO) GOTO 60 RI = RMAT(II) IF (RI .NE. ZERO) GOTO 20 IJ = II C *** SWAP W AND ROW I OF RMAT *** DO 10 J = I, P T = RMAT(IJ) RMAT(IJ) = W(J) W(J) = T IJ = IJ+J 10 CONTINUE T = QTR(I) QTR(I) = Y Y = T GO TO 60 20 IP1 = I+1 IJ = II+I IF ( ABS(WI) .LE. ABS(RI)) GO TO 40 RW = RI/WI T = SQRT(ONE+RW**2) IF (RW .GT. ZERO) T = -T V = RW-T U1 = ONE/T U2 = ONE/(T*V) RMAT(II) = WI*T T = Y+V*QTR(I) QTR(I) = QTR(I)+T*U1 Y = Y+T*U2 IF (IP1 .GT. P) GO TO 60 DO 30 J = IP1, P T = W(J)+V*RMAT(IJ) RMAT(IJ) = RMAT(IJ)+T*U1 W(J) = W(J)+T*U2 IJ = IJ+J 30 CONTINUE GO TO 60 C C *** AT THIS POINT WE MUST HAVE ABS(WI) .LE. ABS(RI)... C 40 WR = WI/RI T = - SQRT(ONE+WR**2) V = WR/(ONE-T) U1 = ONE/T-ONE U2 = V*U1 RMAT(II) = RI*T T = QTR(I)+V*Y QTR(I) = QTR(I)+T*U1 Y = Y+T*U2 IF (IP1 .GT. P) GO TO 60 DO 50 J = IP1, P T = RMAT(IJ)+V*W(J) RMAT(IJ) = RMAT(IJ)+T*U1 W(J) = W(J)+T*U2 IJ = IJ+J 50 CONTINUE 60 CONTINUE 999 RETURN END DOUBLE PRECISION FUNCTION DRLDST(P, D, X, X0) C C *** COMPUTE AND RETURN RELATIVE DIFFERENCE BETWEEN X AND X0 *** C *** NL2SOL VERSION 2.2 *** C INTEGER P DOUBLE PRECISION D(P), X(P), X0(P) C INTEGER I DOUBLE PRECISION EMAX, T, XMAX, ZERO PARAMETER (ZERO=0.D+0) C C *** BODY *** C EMAX = ZERO XMAX = ZERO DO 10 I = 1, P T = ABS(D(I) * (X(I) - X0(I))) IF (EMAX .LT. T) EMAX = T T = D(I) * ( ABS(X(I)) + ABS(X0(I))) IF (XMAX .LT. T) XMAX = T 10 CONTINUE DRLDST = ZERO IF (XMAX .GT. ZERO) DRLDST = EMAX / XMAX 999 RETURN C *** LAST LINE OF DRLDST FOLLOWS *** END SUBROUTINE DS7LUP(A, COSMIN, P, SIZE, STEP, U, W, WCHMTD, WSCALE, 1 Y) C C *** UPDATE SYMMETRIC A SO THAT A * STEP = Y *** C *** (LOWER TRIANGLE OF A STORED ROWWISE *** C C *** PARAMETER DECLARATIONS *** C INTEGER P DOUBLE PRECISION A(1), COSMIN, SIZE, STEP(P), U(P), W(P), 1 WCHMTD(P), WSCALE, Y(P) C DIMENSION A(P*(P+1)/2) C C *** LOCAL VARIABLES *** C INTEGER I, J, K DOUBLE PRECISION DENMIN, SDOTWM, T, UI, WI C C *** CONSTANTS *** DOUBLE PRECISION HALF, ONE, ZERO C C *** EXTERNAL FUNCTIONS AND SUBROUTINES *** C DOUBLE PRECISION DD7TPR, DV2NRM EXTERNAL DD7TPR, DS7LVM, DV2NRM C PARAMETER (HALF=0.5D+0, ONE=1.D+0, ZERO=0.D+0) C C----------------------------------------------------------------------- C SDOTWM = DD7TPR(P, STEP, WCHMTD) DENMIN = COSMIN * DV2NRM(P,STEP) * DV2NRM(P,WCHMTD) WSCALE = ONE IF (DENMIN .NE. ZERO) WSCALE = MIN(ONE, ABS(SDOTWM/DENMIN)) T = ZERO IF (SDOTWM .NE. ZERO) T = WSCALE / SDOTWM DO 10 I = 1, P 10 W(I) = T * WCHMTD(I) CALL DS7LVM(P, U, A, STEP) T = HALF * (SIZE * DD7TPR(P, STEP, U) - DD7TPR(P, STEP, Y)) DO 20 I = 1, P 20 U(I) = T*W(I) + Y(I) - SIZE*U(I) C C *** SET A = A + U*(W**T) + W*(U**T) *** C K = 1 DO 40 I = 1, P UI = U(I) WI = W(I) DO 30 J = 1, I A(K) = SIZE*A(K) + UI*W(J) + WI*U(J) K = K + 1 30 CONTINUE 40 CONTINUE C 999 RETURN C *** LAST LINE OF DS7LUP FOLLOWS *** END SUBROUTINE DS7LVM(P, Y, S, X) C C *** SET Y = S * X, S = P X P SYMMETRIC MATRIX. *** C *** LOWER TRIANGLE OF S STORED ROWWISE. *** C C *** PARAMETER DECLARATIONS *** C INTEGER P DOUBLE PRECISION S(1), X(P), Y(P) C DIMENSION S(P*(P+1)/2) C C *** LOCAL VARIABLES *** C INTEGER I, IM1, J, K DOUBLE PRECISION XI C C C *** EXTERNAL FUNCTION *** C DOUBLE PRECISION DD7TPR EXTERNAL DD7TPR C C----------------------------------------------------------------------- C J = 1 DO 10 I = 1, P Y(I) = DD7TPR(I, S(J), X) J = J + I 10 CONTINUE C IF (P .LE. 1) GO TO 999 J = 1 DO 40 I = 2, P XI = X(I) IM1 = I - 1 J = J + 1 DO 30 K = 1, IM1 Y(K) = Y(K) + S(J)*XI J = J + 1 30 CONTINUE 40 CONTINUE C 999 RETURN C *** LAST LINE OF DS7LVM FOLLOWS *** END SUBROUTINE DV2AXY(P, W, A, X, Y) C C *** SET W = A*X + Y -- W, X, Y = P-VECTORS, A = SCALAR *** C INTEGER P DOUBLE PRECISION A, W(P), X(P), Y(P) C INTEGER I C DO 10 I = 1, P 10 W(I) = A*X(I) + Y(I) RETURN END DOUBLE PRECISION FUNCTION DV2NRM(P, X) C C *** RETURN THE 2-NORM OF THE P-VECTOR X, TAKING *** C *** CARE TO AVOID THE MOST LIKELY UNDERFLOWS. *** C INTEGER P DOUBLE PRECISION X(P) C INTEGER I, J DOUBLE PRECISION ONE, R, SCALE, SQTETA, T, XI, ZERO DOUBLE PRECISION DR7MDC EXTERNAL DR7MDC C PARAMETER (ONE=1.D+0, ZERO=0.D+0) SAVE SQTETA DATA SQTETA/0.D+0/ C IF (P .GT. 0) GO TO 10 DV2NRM = ZERO GO TO 999 10 DO 20 I = 1, P IF (X(I) .NE. ZERO) GO TO 30 20 CONTINUE DV2NRM = ZERO GO TO 999 C 30 SCALE = ABS(X(I)) IF (I .LT. P) GO TO 40 DV2NRM = SCALE GO TO 999 40 T = ONE IF (SQTETA .EQ. ZERO) SQTETA = DR7MDC(2) C C *** SQTETA IS (SLIGHTLY LARGER THAN) THE SQUARE ROOT OF THE C *** SMALLEST POSITIVE FLOATING POINT NUMBER ON THE MACHINE. C *** THE TESTS INVOLVING SQTETA ARE DONE TO PREVENT UNDERFLOWS. C J = I + 1 DO 60 I = J, P XI = ABS(X(I)) IF (XI .GT. SCALE) GO TO 50 R = XI / SCALE IF (R .GT. SQTETA) T = T + R*R GO TO 60 50 R = SCALE / XI IF (R .LE. SQTETA) R = ZERO T = ONE + T * R*R SCALE = XI 60 CONTINUE C DV2NRM = SCALE * SQRT(T) 999 RETURN C *** LAST LINE OF DV2NRM FOLLOWS *** END SUBROUTINE DV7CPY(P, Y, X) C C *** SET Y = X, WHERE X AND Y ARE P-VECTORS *** C INTEGER P DOUBLE PRECISION X(P), Y(P) C INTEGER I C DO 10 I = 1, P 10 Y(I) = X(I) RETURN END SUBROUTINE DV7DFL(ALG, LV, V) C C *** SUPPLY ***SOL (VERSION 2.3) DEFAULT VALUES TO V *** C C *** ALG = 1 MEANS REGRESSION CONSTANTS. C *** ALG = 2 MEANS GENERAL UNCONSTRAINED OPTIMIZATION CONSTANTS. C INTEGER ALG, LV DOUBLE PRECISION V(LV) C DOUBLE PRECISION DR7MDC EXTERNAL DR7MDC C DR7MDC... RETURNS MACHINE-DEPENDENT CONSTANTS C DOUBLE PRECISION MACHEP, MEPCRT, ONE, SQTEPS, THREE C C *** SUBSCRIPTS FOR V *** C INTEGER AFCTOL, BIAS, COSMIN, DECFAC, DELTA0, DFAC, DINIT, DLTFDC, 1 DLTFDJ, DTINIT, D0INIT, EPSLON, ETA0, FUZZ, HUBERC, 2 INCFAC, LMAX0, LMAXS, PHMNFC, PHMXFC, RDFCMN, RDFCMX, 3 RFCTOL, RLIMIT, RSPTOL, SCTOL, SIGMIN, TUNER1, TUNER2, 4 TUNER3, TUNER4, TUNER5, XCTOL, XFTOL C PARAMETER (ONE=1.D+0, THREE=3.D+0) C C *** V SUBSCRIPT VALUES *** C PARAMETER (AFCTOL=31, BIAS=43, COSMIN=47, DECFAC=22, DELTA0=44, 1 DFAC=41, DINIT=38, DLTFDC=42, DLTFDJ=43, DTINIT=39, 2 D0INIT=40, EPSLON=19, ETA0=42, FUZZ=45, HUBERC=48, 3 INCFAC=23, LMAX0=35, LMAXS=36, PHMNFC=20, PHMXFC=21, 4 RDFCMN=24, RDFCMX=25, RFCTOL=32, RLIMIT=46, RSPTOL=49, 5 SCTOL=37, SIGMIN=50, TUNER1=26, TUNER2=27, TUNER3=28, 6 TUNER4=29, TUNER5=30, XCTOL=33, XFTOL=34) C C------------------------------- BODY -------------------------------- C MACHEP = DR7MDC(3) V(AFCTOL) = 1.D-20 IF (MACHEP .GT. 1.D-10) V(AFCTOL) = MACHEP**2 V(DECFAC) = 0.5D+0 SQTEPS = DR7MDC(4) V(DFAC) = 0.6D+0 V(DTINIT) = 1.D-6 MEPCRT = MACHEP ** (ONE/THREE) V(D0INIT) = 1.D+0 V(EPSLON) = 0.1D+0 V(INCFAC) = 2.D+0 V(LMAX0) = 1.D+0 V(LMAXS) = 1.D+0 V(PHMNFC) = -0.1D+0 V(PHMXFC) = 0.1D+0 V(RDFCMN) = 0.1D+0 V(RDFCMX) = 4.D+0 V(RFCTOL) = MAX(1.D-10, MEPCRT**2) V(SCTOL) = V(RFCTOL) V(TUNER1) = 0.1D+0 V(TUNER2) = 1.D-4 V(TUNER3) = 0.75D+0 V(TUNER4) = 0.5D+0 V(TUNER5) = 0.75D+0 V(XCTOL) = SQTEPS V(XFTOL) = 1.D+2 * MACHEP C IF (ALG .GE. 2) GO TO 10 C C *** REGRESSION VALUES C V(COSMIN) = MAX(1.D-6, 1.D+2 * MACHEP) V(DINIT) = 0.D+0 V(DELTA0) = SQTEPS V(DLTFDC) = MEPCRT V(DLTFDJ) = SQTEPS V(FUZZ) = 1.5D+0 V(HUBERC) = 0.7D+0 V(RLIMIT) = DR7MDC(5) V(RSPTOL) = 1.D-3 V(SIGMIN) = 1.D-4 GO TO 999 C C *** GENERAL OPTIMIZATION VALUES C 10 V(BIAS) = 0.8D+0 V(DINIT) = -1.0D+0 V(ETA0) = 1.0D+3 * MACHEP C 999 RETURN C *** LAST LINE OF DV7DFL FOLLOWS *** END SUBROUTINE DV7SCL(N, X, A, Y) C C *** SET X(I) = A*Y(I), I = 1(1)N *** C INTEGER N DOUBLE PRECISION A, X(N), Y(N) C INTEGER I C DO 10 I = 1, N 10 X(I) = A * Y(I) 999 RETURN C *** LAST LINE OF DV7SCL FOLLOWS *** END SUBROUTINE DV7SCP(P, Y, S) C C *** SET P-VECTOR Y TO SCALAR S *** C INTEGER P DOUBLE PRECISION S, Y(P) C INTEGER I C DO 10 I = 1, P 10 Y(I) = S RETURN END DOUBLE PRECISION FUNCTION DVSUM(N, X) INTEGER N DOUBLE PRECISION X(N) INTEGER I C DVSUM = 0.D+0 DO 10 I = 1, N 10 DVSUM = DVSUM + X(I) END LOGICAL FUNCTION STOPX(IDUMMY) C *****PARAMETERS... INTEGER IDUMMY C C .................................................................. C C *****PURPOSE... C THIS FUNCTION MAY SERVE AS THE STOPX (ASYNCHRONOUS INTERRUPTION) C FUNCTION FOR THE NL2SOL (NONLINEAR LEAST-SQUARES) PACKAGE AT C THOSE INSTALLATIONS WHICH DO NOT WISH TO IMPLEMENT A C DYNAMIC STOPX. C C *****ALGORITHM NOTES... C AT INSTALLATIONS WHERE THE NL2SOL SYSTEM IS USED C INTERACTIVELY, THIS DUMMY STOPX SHOULD BE REPLACED BY A C FUNCTION THAT RETURNS .TRUE. IF AND ONLY IF THE INTERRUPT C (BREAK) KEY HAS BEEN PRESSED SINCE THE LAST CALL ON STOPX. C C .................................................................. C STOPX = .FALSE. RETURN END