XLPack 7.0
XLPack Numerical Library (C API) Reference Manual
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◆ zpptrs()

void zpptrs ( char  uplo,
int  n,
int  nrhs,
doublecomplex  ap[],
int  ldb,
doublecomplex  b[],
int *  info 
)

Solution to factorized system of linear equations AX = B for a Hermitian matrix in packed form

Purpose
This routine solves a system of linear equations
A * X = B
with a Hermitian posotive definite matrix A in packed form using the Cholesky factorization A = U^H*U or A = L*L^H computed by zpptrf.
Parameters
[in]uplo= 'U': Upper triangular factor U is stored in ap[].
= 'L': Lower triangular factor L is stored in ap[].
[in]nOrder of the matrix A. (n >= 0) (If n = 0, returns without computation)
[in]nrhsNumber of right hand sides, i.e., number of columns of the matrix B. (nrhs >= 0) (if nrhs = 0, returns without computation)
[in]ap[]Array ap[lap] (lap >= n(n + 1)/2)
The triangular factor U or L in packed form from the Cholesky factorization A = U^H*U or A = L*L^H, as computed by zpptrf.
[in]ldbLeading dimension of the two dimensional array b[][]. (ldb >= max(1, n))
[in,out]b[][]Array b[lb][ldb] (lb >= nrhs)
[in] Right hand side matrix B.
[out] Solution matrix X.
[out]info= 0: Successful exit
= -1: The argument uplo had an illegal value (uplo != 'U' nor 'L')
= -2: The argument n had an illegal value (n < 0)
= -3: The argument nrhs had an illegal value (nrhs < 0)
= -5: The argument ldb had an illegal value (ldb < max(1, n))
Reference
LAPACK