117 lines
2.9 KiB
FortranFixed
117 lines
2.9 KiB
FortranFixed
SUBROUTINE CQRT13( SCALE, M, N, A, LDA, NORMA, ISEED )
|
|
*
|
|
* -- LAPACK test routine (version 3.1) --
|
|
* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
|
|
* October 2006
|
|
*
|
|
* .. Scalar Arguments ..
|
|
INTEGER LDA, M, N, SCALE
|
|
REAL NORMA
|
|
* ..
|
|
* .. Array Arguments ..
|
|
INTEGER ISEED( 4 )
|
|
COMPLEX A( LDA, * )
|
|
* ..
|
|
*
|
|
* Purpose
|
|
* =======
|
|
*
|
|
* CQRT13 generates a full-rank matrix that may be scaled to have large
|
|
* or small norm.
|
|
*
|
|
* Arguments
|
|
* =========
|
|
*
|
|
* SCALE (input) INTEGER
|
|
* SCALE = 1: normally scaled matrix
|
|
* SCALE = 2: matrix scaled up
|
|
* SCALE = 3: matrix scaled down
|
|
*
|
|
* M (input) INTEGER
|
|
* The number of rows of the matrix A.
|
|
*
|
|
* N (input) INTEGER
|
|
* The number of columns of A.
|
|
*
|
|
* A (output) COMPLEX array, dimension (LDA,N)
|
|
* The M-by-N matrix A.
|
|
*
|
|
* LDA (input) INTEGER
|
|
* The leading dimension of the array A.
|
|
*
|
|
* NORMA (output) REAL
|
|
* The one-norm of A.
|
|
*
|
|
* ISEED (input/output) integer array, dimension (4)
|
|
* Seed for random number generator
|
|
*
|
|
* =====================================================================
|
|
*
|
|
* .. Parameters ..
|
|
REAL ONE
|
|
PARAMETER ( ONE = 1.0E0 )
|
|
* ..
|
|
* .. Local Scalars ..
|
|
INTEGER INFO, J
|
|
REAL BIGNUM, SMLNUM
|
|
* ..
|
|
* .. External Functions ..
|
|
REAL CLANGE, SCASUM, SLAMCH
|
|
EXTERNAL CLANGE, SCASUM, SLAMCH
|
|
* ..
|
|
* .. External Subroutines ..
|
|
EXTERNAL CLARNV, CLASCL, SLABAD
|
|
* ..
|
|
* .. Intrinsic Functions ..
|
|
INTRINSIC CMPLX, REAL, SIGN
|
|
* ..
|
|
* .. Local Arrays ..
|
|
REAL DUMMY( 1 )
|
|
* ..
|
|
* .. Executable Statements ..
|
|
*
|
|
IF( M.LE.0 .OR. N.LE.0 )
|
|
$ RETURN
|
|
*
|
|
* benign matrix
|
|
*
|
|
DO 10 J = 1, N
|
|
CALL CLARNV( 2, ISEED, M, A( 1, J ) )
|
|
IF( J.LE.M ) THEN
|
|
A( J, J ) = A( J, J ) + CMPLX( SIGN( SCASUM( M, A( 1, J ),
|
|
$ 1 ), REAL( A( J, J ) ) ) )
|
|
END IF
|
|
10 CONTINUE
|
|
*
|
|
* scaled versions
|
|
*
|
|
IF( SCALE.NE.1 ) THEN
|
|
NORMA = CLANGE( 'Max', M, N, A, LDA, DUMMY )
|
|
SMLNUM = SLAMCH( 'Safe minimum' )
|
|
BIGNUM = ONE / SMLNUM
|
|
CALL SLABAD( SMLNUM, BIGNUM )
|
|
SMLNUM = SMLNUM / SLAMCH( 'Epsilon' )
|
|
BIGNUM = ONE / SMLNUM
|
|
*
|
|
IF( SCALE.EQ.2 ) THEN
|
|
*
|
|
* matrix scaled up
|
|
*
|
|
CALL CLASCL( 'General', 0, 0, NORMA, BIGNUM, M, N, A, LDA,
|
|
$ INFO )
|
|
ELSE IF( SCALE.EQ.3 ) THEN
|
|
*
|
|
* matrix scaled down
|
|
*
|
|
CALL CLASCL( 'General', 0, 0, NORMA, SMLNUM, M, N, A, LDA,
|
|
$ INFO )
|
|
END IF
|
|
END IF
|
|
*
|
|
NORMA = CLANGE( 'One-norm', M, N, A, LDA, DUMMY )
|
|
RETURN
|
|
*
|
|
* End of CQRT13
|
|
*
|
|
END
|