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SUBROUTINE ZLAIPD( N, A, INDA, VINDA )
*
* -- LAPACK test routine (version 3.1) --
* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
* November 2006
*
* .. Scalar Arguments ..
INTEGER INDA, N, VINDA
* ..
* .. Array Arguments ..
COMPLEX*16 A( * )
* ..
*
* Purpose
* =======
*
* ZLAIPD sets the imaginary part of the diagonal elements of a complex
* matrix A to a large value. This is used to test LAPACK routines for
* complex Hermitian matrices, which are not supposed to access or use
* the imaginary parts of the diagonals.
*
* Arguments
* =========
*
* N (input) INTEGER
* The number of diagonal elements of A.
*
* A (input/output) COMPLEX*16 array, dimension
* (1+(N-1)*INDA+(N-2)*VINDA)
* On entry, the complex (Hermitian) matrix A.
* On exit, the imaginary parts of the diagonal elements are set
* to BIGNUM = EPS / SAFMIN, where EPS is the machine epsilon and
* SAFMIN is the safe minimum.
*
* INDA (input) INTEGER
* The increment between A(1) and the next diagonal element of A.
* Typical values are
* = LDA+1: square matrices with leading dimension LDA
* = 2: packed upper triangular matrix, starting at A(1,1)
* = N: packed lower triangular matrix, starting at A(1,1)
*
* VINDA (input) INTEGER
* The change in the diagonal increment between columns of A.
* Typical values are
* = 0: no change, the row and column increments in A are fixed
* = 1: packed upper triangular matrix
* = -1: packed lower triangular matrix
*
* =====================================================================
*
* .. Local Scalars ..
INTEGER I, IA, IXA
DOUBLE PRECISION BIGNUM
* ..
* .. External Functions ..
DOUBLE PRECISION DLAMCH
EXTERNAL DLAMCH
* ..
* .. Intrinsic Functions ..
INTRINSIC DBLE, DCMPLX
* ..
* .. Executable Statements ..
*
BIGNUM = DLAMCH( 'Epsilon' ) / DLAMCH( 'Safe minimum' )
IA = 1
IXA = INDA
DO 10 I = 1, N
A( IA ) = DCMPLX( DBLE( A( IA ) ), BIGNUM )
IA = IA + IXA
IXA = IXA + VINDA
10 CONTINUE
RETURN
END
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