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Diffstat (limited to 'src/lib/lapack/dspev.f')
| -rw-r--r-- | src/lib/lapack/dspev.f | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/src/lib/lapack/dspev.f b/src/lib/lapack/dspev.f deleted file mode 100644 index 64582c99..00000000 --- a/src/lib/lapack/dspev.f +++ /dev/null @@ -1,187 +0,0 @@ - SUBROUTINE DSPEV( JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO ) -* -* -- LAPACK driver routine (version 3.1) -- -* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. -* November 2006 -* -* .. Scalar Arguments .. - CHARACTER JOBZ, UPLO - INTEGER INFO, LDZ, N -* .. -* .. Array Arguments .. - DOUBLE PRECISION AP( * ), W( * ), WORK( * ), Z( LDZ, * ) -* .. -* -* Purpose -* ======= -* -* DSPEV computes all the eigenvalues and, optionally, eigenvectors of a -* real symmetric matrix A in packed storage. -* -* Arguments -* ========= -* -* JOBZ (input) CHARACTER*1 -* = 'N': Compute eigenvalues only; -* = 'V': Compute eigenvalues and eigenvectors. -* -* UPLO (input) CHARACTER*1 -* = 'U': Upper triangle of A is stored; -* = 'L': Lower triangle of A is stored. -* -* N (input) INTEGER -* The order of the matrix A. N >= 0. -* -* AP (input/output) DOUBLE PRECISION array, dimension (N*(N+1)/2) -* On entry, the upper or lower triangle of the symmetric matrix -* A, packed columnwise in a linear array. The j-th column of A -* is stored in the array AP as follows: -* if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; -* if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n. -* -* On exit, AP is overwritten by values generated during the -* reduction to tridiagonal form. If UPLO = 'U', the diagonal -* and first superdiagonal of the tridiagonal matrix T overwrite -* the corresponding elements of A, and if UPLO = 'L', the -* diagonal and first subdiagonal of T overwrite the -* corresponding elements of A. -* -* W (output) DOUBLE PRECISION array, dimension (N) -* If INFO = 0, the eigenvalues in ascending order. -* -* Z (output) DOUBLE PRECISION array, dimension (LDZ, N) -* If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal -* eigenvectors of the matrix A, with the i-th column of Z -* holding the eigenvector associated with W(i). -* If JOBZ = 'N', then Z is not referenced. -* -* LDZ (input) INTEGER -* The leading dimension of the array Z. LDZ >= 1, and if -* JOBZ = 'V', LDZ >= max(1,N). -* -* WORK (workspace) DOUBLE PRECISION array, dimension (3*N) -* -* INFO (output) INTEGER -* = 0: successful exit. -* < 0: if INFO = -i, the i-th argument had an illegal value. -* > 0: if INFO = i, the algorithm failed to converge; i -* off-diagonal elements of an intermediate tridiagonal -* form did not converge to zero. -* -* ===================================================================== -* -* .. Parameters .. - DOUBLE PRECISION ZERO, ONE - PARAMETER ( ZERO = 0.0D0, ONE = 1.0D0 ) -* .. -* .. Local Scalars .. - LOGICAL WANTZ - INTEGER IINFO, IMAX, INDE, INDTAU, INDWRK, ISCALE - DOUBLE PRECISION ANRM, BIGNUM, EPS, RMAX, RMIN, SAFMIN, SIGMA, - $ SMLNUM -* .. -* .. External Functions .. - LOGICAL LSAME - DOUBLE PRECISION DLAMCH, DLANSP - EXTERNAL LSAME, DLAMCH, DLANSP -* .. -* .. External Subroutines .. - EXTERNAL DOPGTR, DSCAL, DSPTRD, DSTEQR, DSTERF, XERBLA -* .. -* .. Intrinsic Functions .. - INTRINSIC SQRT -* .. -* .. Executable Statements .. -* -* Test the input parameters. -* - WANTZ = LSAME( JOBZ, 'V' ) -* - INFO = 0 - IF( .NOT.( WANTZ .OR. LSAME( JOBZ, 'N' ) ) ) THEN - INFO = -1 - ELSE IF( .NOT.( LSAME( UPLO, 'U' ) .OR. LSAME( UPLO, 'L' ) ) ) - $ THEN - INFO = -2 - ELSE IF( N.LT.0 ) THEN - INFO = -3 - ELSE IF( LDZ.LT.1 .OR. ( WANTZ .AND. LDZ.LT.N ) ) THEN - INFO = -7 - END IF -* - IF( INFO.NE.0 ) THEN - CALL XERBLA( 'DSPEV ', -INFO ) - RETURN - END IF -* -* Quick return if possible -* - IF( N.EQ.0 ) - $ RETURN -* - IF( N.EQ.1 ) THEN - W( 1 ) = AP( 1 ) - IF( WANTZ ) - $ Z( 1, 1 ) = ONE - RETURN - END IF -* -* Get machine constants. -* - SAFMIN = DLAMCH( 'Safe minimum' ) - EPS = DLAMCH( 'Precision' ) - SMLNUM = SAFMIN / EPS - BIGNUM = ONE / SMLNUM - RMIN = SQRT( SMLNUM ) - RMAX = SQRT( BIGNUM ) -* -* Scale matrix to allowable range, if necessary. -* - ANRM = DLANSP( 'M', UPLO, N, AP, WORK ) - ISCALE = 0 - IF( ANRM.GT.ZERO .AND. ANRM.LT.RMIN ) THEN - ISCALE = 1 - SIGMA = RMIN / ANRM - ELSE IF( ANRM.GT.RMAX ) THEN - ISCALE = 1 - SIGMA = RMAX / ANRM - END IF - IF( ISCALE.EQ.1 ) THEN - CALL DSCAL( ( N*( N+1 ) ) / 2, SIGMA, AP, 1 ) - END IF -* -* Call DSPTRD to reduce symmetric packed matrix to tridiagonal form. -* - INDE = 1 - INDTAU = INDE + N - CALL DSPTRD( UPLO, N, AP, W, WORK( INDE ), WORK( INDTAU ), IINFO ) -* -* For eigenvalues only, call DSTERF. For eigenvectors, first call -* DOPGTR to generate the orthogonal matrix, then call DSTEQR. -* - IF( .NOT.WANTZ ) THEN - CALL DSTERF( N, W, WORK( INDE ), INFO ) - ELSE - INDWRK = INDTAU + N - CALL DOPGTR( UPLO, N, AP, WORK( INDTAU ), Z, LDZ, - $ WORK( INDWRK ), IINFO ) - CALL DSTEQR( JOBZ, N, W, WORK( INDE ), Z, LDZ, WORK( INDTAU ), - $ INFO ) - END IF -* -* If matrix was scaled, then rescale eigenvalues appropriately. -* - IF( ISCALE.EQ.1 ) THEN - IF( INFO.EQ.0 ) THEN - IMAX = N - ELSE - IMAX = INFO - 1 - END IF - CALL DSCAL( IMAX, ONE / SIGMA, W, 1 ) - END IF -* - RETURN -* -* End of DSPEV -* - END |