cpptrs(3P) Sun Performance Library cpptrs(3P)NAMEcpptrs - solve a system of linear equations A*X = B with a Hermitian
positive definite matrix A in packed storage using the Cholesky factor‐
ization A = U**H*U or A = L*L**H computed by CPPTRF
SYNOPSIS
SUBROUTINE CPPTRS(UPLO, N, NRHS, A, B, LDB, INFO)
CHARACTER * 1 UPLO
COMPLEX A(*), B(LDB,*)
INTEGER N, NRHS, LDB, INFO
SUBROUTINE CPPTRS_64(UPLO, N, NRHS, A, B, LDB, INFO)
CHARACTER * 1 UPLO
COMPLEX A(*), B(LDB,*)
INTEGER*8 N, NRHS, LDB, INFO
F95 INTERFACE
SUBROUTINE PPTRS(UPLO, [N], [NRHS], A, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
COMPLEX, DIMENSION(:) :: A
COMPLEX, DIMENSION(:,:) :: B
INTEGER :: N, NRHS, LDB, INFO
SUBROUTINE PPTRS_64(UPLO, [N], [NRHS], A, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
COMPLEX, DIMENSION(:) :: A
COMPLEX, DIMENSION(:,:) :: B
INTEGER(8) :: N, NRHS, LDB, INFO
C INTERFACE
#include <sunperf.h>
void cpptrs(char uplo, int n, int nrhs, complex *a, complex *b, int
ldb, int *info);
void cpptrs_64(char uplo, long n, long nrhs, complex *a, complex *b,
long ldb, long *info);
PURPOSEcpptrs solves a system of linear equations A*X = B with a Hermitian
positive definite matrix A in packed storage using the Cholesky factor‐
ization A = U**H*U or A = L*L**H computed by CPPTRF.
ARGUMENTS
UPLO (input)
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
N (input) The order of the matrix A. N >= 0.
NRHS (input)
The number of right hand sides, i.e., the number of columns
of the matrix B. NRHS >= 0.
A (input) COMPLEX array, dimension (N*(N+1)/2)
The triangular factor U or L from the Cholesky factorization
A = U**H*U or A = L*L**H, packed columnwise in a linear
array. The j-th column of U or L is stored in the array A as
follows: if UPLO = 'U', A(i + (j-1)*j/2) = U(i,j) for
1<=i<=j; if UPLO = 'L', A(i + (j-1)*(2n-j)/2) = L(i,j) for
j<=i<=n.
B (input/output) COMPLEX array, dimension (LDB,NRHS)
On entry, the right hand side matrix B. On exit, the solu‐
tion matrix X.
LDB (input)
The leading dimension of the array B. LDB >= max(1,N).
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
6 Mar 2009 cpptrs(3P)
