00001 SUBROUTINE ZLAIPD( N, A, INDA, VINDA ) 00002 * 00003 * -- LAPACK test routine (version 3.1) -- 00004 * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. 00005 * November 2006 00006 * 00007 * .. Scalar Arguments .. 00008 INTEGER INDA, N, VINDA 00009 * .. 00010 * .. Array Arguments .. 00011 COMPLEX*16 A( * ) 00012 * .. 00013 * 00014 * Purpose 00015 * ======= 00016 * 00017 * ZLAIPD sets the imaginary part of the diagonal elements of a complex 00018 * matrix A to a large value. This is used to test LAPACK routines for 00019 * complex Hermitian matrices, which are not supposed to access or use 00020 * the imaginary parts of the diagonals. 00021 * 00022 * Arguments 00023 * ========= 00024 * 00025 * N (input) INTEGER 00026 * The number of diagonal elements of A. 00027 * 00028 * A (input/output) COMPLEX*16 array, dimension 00029 * (1+(N-1)*INDA+(N-2)*VINDA) 00030 * On entry, the complex (Hermitian) matrix A. 00031 * On exit, the imaginary parts of the diagonal elements are set 00032 * to BIGNUM = EPS / SAFMIN, where EPS is the machine epsilon and 00033 * SAFMIN is the safe minimum. 00034 * 00035 * INDA (input) INTEGER 00036 * The increment between A(1) and the next diagonal element of A. 00037 * Typical values are 00038 * = LDA+1: square matrices with leading dimension LDA 00039 * = 2: packed upper triangular matrix, starting at A(1,1) 00040 * = N: packed lower triangular matrix, starting at A(1,1) 00041 * 00042 * VINDA (input) INTEGER 00043 * The change in the diagonal increment between columns of A. 00044 * Typical values are 00045 * = 0: no change, the row and column increments in A are fixed 00046 * = 1: packed upper triangular matrix 00047 * = -1: packed lower triangular matrix 00048 * 00049 * ===================================================================== 00050 * 00051 * .. Local Scalars .. 00052 INTEGER I, IA, IXA 00053 DOUBLE PRECISION BIGNUM 00054 * .. 00055 * .. External Functions .. 00056 DOUBLE PRECISION DLAMCH 00057 EXTERNAL DLAMCH 00058 * .. 00059 * .. Intrinsic Functions .. 00060 INTRINSIC DBLE, DCMPLX 00061 * .. 00062 * .. Executable Statements .. 00063 * 00064 BIGNUM = DLAMCH( 'Epsilon' ) / DLAMCH( 'Safe minimum' ) 00065 IA = 1 00066 IXA = INDA 00067 DO 10 I = 1, N 00068 A( IA ) = DCMPLX( DBLE( A( IA ) ), BIGNUM ) 00069 IA = IA + IXA 00070 IXA = IXA + VINDA 00071 10 CONTINUE 00072 RETURN 00073 END
1.7.2