* F04AFF Example Program Text * Mark 14 Revised. NAG Copyright 1989. * .. Parameters .. INTEGER NMAX, IR, IA, IB, IX, IBB PARAMETER (NMAX=8,IR=1,IA=NMAX,IB=NMAX,IX=NMAX,IBB=NMAX) INTEGER NIN, NOUT PARAMETER (NIN=5,NOUT=6) * .. Local Scalars .. DOUBLE PRECISION D1, EPS INTEGER I, ID, IFAIL, J, K, N * .. Local Arrays .. DOUBLE PRECISION A(IA,NMAX), B(IB,IR), BB(IBB,IR), P(NMAX), + X(IX,IR) * .. External Functions .. DOUBLE PRECISION X02AJF EXTERNAL X02AJF * .. External Subroutines .. EXTERNAL F03AEF, F04AFF * .. Executable Statements .. WRITE (NOUT,*) 'F04AFF Example Program Results' * Skip heading in data file READ (NIN,*) READ (NIN,*) N WRITE (NOUT,*) IF (N.GT.0 .AND. N.LE.NMAX) THEN READ (NIN,*) ((A(I,J),J=1,N),I=1,N) IFAIL = 1 * * Cholesky decomposition CALL F03AEF(N,A,IA,P,D1,ID,IFAIL) * IF (IFAIL.NE.0) THEN WRITE (NOUT,99999) 'Error in F03AEF. IFAIL =', IFAIL ELSE READ (NIN,*) ((B(I,J),J=1,IR),I=1,N) EPS = X02AJF() IFAIL = 1 * * Accurate solution of linear equations CALL F04AFF(N,IR,A,IA,P,B,IB,EPS,X,IX,BB,IBB,K,IFAIL) * IF (IFAIL.NE.0) THEN WRITE (NOUT,99999) 'Error in F04AFF. IFAIL =', IFAIL ELSE WRITE (NOUT,*) ' Solution' DO 20 I = 1, N WRITE (NOUT,99998) (X(I,J),J=1,IR) 20 CONTINUE END IF END IF ELSE WRITE (NOUT,99999) 'N is out of range: N = ', N END IF STOP * 99999 FORMAT (1X,A,I5) 99998 FORMAT (1X,8F9.4) END