* F07HDF Example Program Text * Mark 15 Release. NAG Copyright 1991. * .. Parameters .. INTEGER NIN, NOUT PARAMETER (NIN=5,NOUT=6) INTEGER NMAX, KMAX, LDAB PARAMETER (NMAX=8,KMAX=8,LDAB=KMAX+1) * .. Local Scalars .. INTEGER I, IFAIL, INFO, J, KD, N CHARACTER UPLO * .. Local Arrays .. DOUBLE PRECISION AB(LDAB,NMAX) * .. External Subroutines .. EXTERNAL DPBTRF, X04CEF * .. Intrinsic Functions .. INTRINSIC MAX, MIN * .. Executable Statements .. WRITE (NOUT,*) 'F07HDF Example Program Results' * Skip heading in data file READ (NIN,*) READ (NIN,*) N, KD IF (N.LE.NMAX .AND. KD.LE.KMAX) THEN * * Read A from data file * READ (NIN,*) UPLO IF (UPLO.EQ.'U') THEN DO 20 I = 1, N READ (NIN,*) (AB(KD+1+I-J,J),J=I,MIN(N,I+KD)) 20 CONTINUE ELSE IF (UPLO.EQ.'L') THEN DO 40 I = 1, N READ (NIN,*) (AB(1+I-J,J),J=MAX(1,I-KD),I) 40 CONTINUE END IF * * Factorize A * CALL DPBTRF(UPLO,N,KD,AB,LDAB,INFO) * WRITE (NOUT,*) IF (INFO.EQ.0) THEN * * Print factor * IFAIL = 0 * IF (UPLO.EQ.'U') THEN * CALL X04CEF(N,N,0,KD,AB,LDAB,'Factor',IFAIL) * ELSE IF (UPLO.EQ.'L') THEN * CALL X04CEF(N,N,KD,0,AB,LDAB,'Factor',IFAIL) * END IF * ELSE WRITE (NOUT,*) 'A is not positive-definite' END IF END IF * END