CHPTRS(l) ) CHPTRS(l)NAME
CHPTRS - solve a system of linear equations A*X = B with a complex Her‐
mitian matrix A stored in packed format using the factorization A =
U*D*U**H or A = L*D*L**H computed by CHPTRF
SYNOPSIS
SUBROUTINE CHPTRS( UPLO, N, NRHS, AP, IPIV, B, LDB, INFO )
CHARACTER UPLO
INTEGER INFO, LDB, N, NRHS
INTEGER IPIV( * )
COMPLEX AP( * ), B( LDB, * )
PURPOSE
CHPTRS solves a system of linear equations A*X = B with a complex Her‐
mitian matrix A stored in packed format using the factorization A =
U*D*U**H or A = L*D*L**H computed by CHPTRF.
ARGUMENTS
UPLO (input) CHARACTER*1
Specifies whether the details of the factorization are stored
as an upper or lower triangular matrix. = 'U': Upper triangu‐
lar, form is A = U*D*U**H;
= 'L': Lower triangular, form is A = L*D*L**H.
N (input) INTEGER
The order of the matrix A. N >= 0.
NRHS (input) INTEGER
The number of right hand sides, i.e., the number of columns of
the matrix B. NRHS >= 0.
AP (input) COMPLEX array, dimension (N*(N+1)/2)
The block diagonal matrix D and the multipliers used to obtain
the factor U or L as computed by CHPTRF, stored as a packed
triangular matrix.
IPIV (input) INTEGER array, dimension (N)
Details of the interchanges and the block structure of D as
determined by CHPTRF.
B (input/output) COMPLEX array, dimension (LDB,NRHS)
On entry, the right hand side matrix B. On exit, the solution
matrix X.
LDB (input) INTEGER
The leading dimension of the array B. LDB >= max(1,N).
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
LAPACK version 3.0 15 June 2000 CHPTRS(l)
