|
PROGRAM TEST
|
IMPLICIT NONE
|
C
|
DOUBLE PRECISION ZERO
|
INTEGER LDA, LDWORK, N
|
PARAMETER (N = 3)
|
PARAMETER (LDA = N)
|
PARAMETER (LDWORK = 2 * N)
|
PARAMETER (ZERO = 0.0D0)
|
C
|
COMPLEX*16 A(LDA,N), WORK(LDWORK)
|
INTEGER ICOL, INFO, IPIVOT(N), IROW
|
C
|
EXTERNAL ZHETRF, ZHETRI
|
INTRINSIC ABS, CMPLX, CONJG, DBLE
|
C
|
C Initialize the array A to store the coefficient array A
|
C shown below.
|
C
|
C 1 1-i 1-i
|
C A = 1+i 3 3-i
|
C 1+i 3+i 5
|
C
|
DATA A / (1.0D0,8D8), (8D8,8D8), (8D8,8D8),
|
$ (1.0D0,-1.0D0), (3.0D0,8D8), (8D8,8D8),
|
$ (1.0D0,-1.0D0), (3.0D0,-1.0D0), (5.0D0,8D8) /
|
C
|
C Print the initial value of A.
|
C
|
PRINT 1000
|
DO 100, IROW = 1, N
|
PRINT 1010, (CONJG(A(ICOL,IROW)), ICOL = 1, IROW - 1),
|
$ CMPLX(DBLE(A(IROW,IROW)), ZERO),
|
$ (A(IROW,ICOL), ICOL = IROW + 1, N)
|
100 CONTINUE
|
PRINT 1020
|
DO 110, IROW = 1, N
|
PRINT 1010, (A(IROW,ICOL), ICOL = 1, N)
|
110 CONTINUE
|
C
|
C Factor the matrix.
|
C
|
CALL ZHETRF ('UPPER TRIANGLE OF A STORED', N, A, LDA,
|
$ IPIVOT, WORK, LDWORK, INFO)
|
IF (INFO .LT. 0) THEN
|
PRINT 1040, ABS(INFO)
|
STOP 1
|
ELSE IF (INFO .GT. 0) THEN
|
PRINT 1050
|
STOP 2
|
END IF
|
C
|
C Compute and print the inverse.
|
C
|
CALL ZHETRI ('UPPER TRIANGULAR FACTOR OF A', N, A, LDA,
|
$ IPIVOT, WORK, INFO)
|
IF (INFO .LT. 0) THEN
|
PRINT 1060, ABS(INFO)
|
STOP 3
|
END IF
|
PRINT 1070
|
DO 200, IROW = 1, N
|
PRINT 1010, (CONJG(A(ICOL,IROW)), ICOL = 1, IROW - 1),
|
$ (A(IROW,ICOL), ICOL = IROW, N)
|
200 CONTINUE
|
C
|
1000 FORMAT (1X, 'A in full form:')
|
1010 FORMAT (1X, 10(: 2X, '(', F5.1, ',', F5.1, ')'))
|
1020 FORMAT (/1X, 'A in Hermitian form: (* in unused entries)')
|
1030 FORMAT (/1X, 'b:')
|
1040 FORMAT (1X, 'Illegal argument to ZHETRF, argument #', I2)
|
1050 FORMAT (1X, 'A is singular to working precision.')
|
1060 FORMAT (1X, 'Illegal argument to ZHETRI, argument #', I2)
|
1070 FORMAT (/1X, 'A**(-1):')
|
C
|
END
|
|