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.. * November 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