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DOUBLE PRECISION FUNCTION ZLA_GBRPVGRW( N, KL, KU, NCOLS, AB,
$ LDAB, AFB, LDAFB )
*
* -- LAPACK routine (version 3.2) --
* -- Contributed by James Demmel, Deaglan Halligan, Yozo Hida and --
* -- Jason Riedy of Univ. of California Berkeley. --
* -- November 2008 --
*
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley and NAG Ltd. --
*
IMPLICIT NONE
* ..
* .. Scalar Arguments ..
INTEGER N, KL, KU, NCOLS, LDAB, LDAFB
* ..
* .. Array Arguments ..
COMPLEX*16 AB( LDAB, * ), AFB( LDAFB, * )
* ..
*
* Purpose
* =======
*
* ZLA_GBRPVGRW computes ... .
*
* Arguments
* =========
*
* =====================================================================
*
* .. Local Scalars ..
INTEGER I, J, KD
DOUBLE PRECISION AMAX, UMAX, RPVGRW
COMPLEX*16 ZDUM
* ..
* .. Intrinsic Functions ..
INTRINSIC ABS, MAX, MIN, REAL, DIMAG
* ..
* .. Statement Functions ..
DOUBLE PRECISION CABS1
* ..
* .. Statement Function Definitions ..
CABS1( ZDUM ) = ABS( DBLE( ZDUM ) ) + ABS( DIMAG( ZDUM ) )
* ..
* .. Executable Statements ..
*
RPVGRW = 1.0D+0
*
KD = KU + 1
DO J = 1, NCOLS
AMAX = 0.0D+0
UMAX = 0.0D+0
DO I = MAX( J-KU, 1 ), MIN( J+KL, N )
AMAX = MAX( CABS1( AB( KD+I-J, J ) ), AMAX )
END DO
DO I = MAX( J-KU, 1 ), J
UMAX = MAX( CABS1( AFB( KD+I-J, J ) ), UMAX )
END DO
IF ( UMAX /= 0.0D+0 ) THEN
RPVGRW = MIN( AMAX / UMAX, RPVGRW )
END IF
END DO
ZLA_GBRPVGRW = RPVGRW
END FUNCTION
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