|
PROGRAM TEST
|
IMPLICIT NONE
|
C
|
INTEGER LDEVAL, LDEVEC, LDWORK, LDWRK2, LENGTA, N
|
PARAMETER (N = 3)
|
PARAMETER (LDEVAL = N)
|
PARAMETER (LDEVEC = N)
|
PARAMETER (LDWORK = 2 * N - 1)
|
PARAMETER (LDWRK2 = 3 * N - 2)
|
PARAMETER (LENGTA = (N * N + N) / 2)
|
C
|
DOUBLE PRECISION EVALS(LDEVAL), WORK2(LDWRK2)
|
COMPLEX*16 A(LENGTA), EVECS(LDEVEC,N), WORK(LDWORK)
|
INTEGER ICOL, INFO, IROW
|
C
|
EXTERNAL ZHPEV
|
INTRINSIC ABS, CONJG
|
C
|
C Initialize the array A to store the coefficient array A
|
C shown below.
|
C
|
C 4 4-4i 0
|
C A = 4+4i 4 4-4i
|
C 0 4+4i 4
|
C
|
DATA A / (4.0D0,0.0D0), (4.0D0,-4.0D0), (4.0D0,0.0D0),
|
$ (0.0D0,0.0D0), (4.0D0,-4.0D0), (4.0D0,0.0D0) /
|
C
|
C Print the initial value of A.
|
C
|
PRINT 1000
|
PRINT 1010, A(1), A(2), A(4)
|
PRINT 1010, CONJG(A(2)), A(3), A(5)
|
PRINT 1010, CONJG(A(4)), CONJG(A(5)), A(6)
|
C
|
C Compute the eigenvalues and eigenvectors.
|
C
|
CALL ZHPEV ('VALUES AND VECTORS, EIGEN',
|
$ 'UPPER TRIANGLE OF A STORED', N, A, EVALS,
|
$ EVECS, LDEVEC, WORK, WORK2, INFO)
|
IF (INFO .LT. 0) THEN
|
PRINT 1020, ABS(INFO)
|
STOP 1
|
ELSE IF (INFO .GT. 0) THEN
|
PRINT 1030, INFO
|
STOP 2
|
END IF
|
C
|
C Print the eigenvalues and eigenvectors.
|
C
|
PRINT 1040
|
DO 200, IROW = 1, N
|
PRINT 1050, EVALS(IROW), (EVECS(IROW,ICOL), ICOL = 1, N)
|
200 CONTINUE
|
C
|
1000 FORMAT (1X, 'A:')
|
1010 FORMAT (1X, 10(: 2X, '(', F5.1, ',', F5.1, ')'))
|
1020 FORMAT (1X, 'Illegal argument to ZHPEV, argument #', I2)
|
1030 FORMAT (1X, 'Convergence failure, INFO = ', I2)
|
1040 FORMAT (/1X, 'Eigenvalue', 16X, 'Eigenvector**T')
|
1050 FORMAT (1X, F8.3, 6X, '[', 3('(', F4.1, ',', F4.1, ') '),
|
$ ']')
|
C
|
END
|
|