?ptsv

Developer Reference for Intel® oneAPI Math Kernel Library for C

Download PDF

ID 766684

Date 4/28/2026

Version

Public

?ptsv

Computes the solution to the system of linear equations with a symmetric or Hermitian positive definite tridiagonal coefficient matrix A and multiple right-hand sides.

Syntax

lapack_int LAPACKE_sptsv ( intmatrix_layout , lapack_intn , lapack_intnrhs , float*d , float*e , float*b , lapack_intldb );

lapack_int LAPACKE_dptsv ( intmatrix_layout , lapack_intn , lapack_intnrhs , double*d , double*e , double*b , lapack_intldb );

lapack_int LAPACKE_cptsv ( intmatrix_layout , lapack_intn , lapack_intnrhs , float*d , lapack_complex_float*e , lapack_complex_float*b , lapack_intldb );

lapack_int LAPACKE_zptsv ( intmatrix_layout , lapack_intn , lapack_intnrhs , double*d , lapack_complex_double*e , lapack_complex_double*b , lapack_intldb );

Include Files

mkl.h

Description

sptsv dptsv cptsv zptsv ptsv

The routine solves for X the real or complex system of linear equations A*X = B , where A is an n -by- n symmetric/Hermitian positive-definite tridiagonal matrix, the columns of matrix B are individual right-hand sides, and the columns of X are the corresponding solutions.

A is factored as A = L*D*L^{T} (real flavors) or A = L*D*L^{H} (complex flavors), and the factored form of A is then used to solve the system of equations A*X = B .

Input Parameters

matrix_layout

Specifies whether matrix storage layout is row major ( LAPACK_ROW_MAJOR ) or column major ( LAPACK_COL_MAJOR ).

n

The order of matrix A ; n ≥ 0.

nrhs

The number of right-hand sides, the number of columns in B; nrhs≥ 0 .

d

Array, dimension at least max(1, n) . Contains the diagonal elements of the tridiagonal matrix A .

e , b

Arrays: e (size n - 1), b of size max(1, ldb * nrhs ) for column major layout and max(1, ldb * n ) for row major layout . The array e contains the (n - 1) subdiagonal elements of A .

The array b contains the matrix B whose columns are the right-hand sides for the systems of equations.

ldb

The leading dimension of b ; ldb≥ max(1, n)ldb ≥ max(1, n ) for column major layout and ldb ≥ nrhs for row major layout .

Output Parameters

d

Overwritten by the n diagonal elements of the diagonal matrix D from the L*D*L^{T} (real)/ L*D*L^{H} (complex) factorization of A .

e

Overwritten by the (n - 1) subdiagonal elements of the unit bidiagonal factor L from the factorization of A .

b

Overwritten by the solution matrix X .

Return Values

This function returns a value info .

If info = 0 , the execution is successful.
If info = -i , parameter i had an illegal value.
If info = i , the leading minor of order i (and therefore the matrix A itself) is not positive-definite, and the solution has not been computed. The factorization has not been completed unless i = n .

LAPACK 95 Interface Notes

There exist FORTRAN 77 and FORTRAN 95 interfaces for this routine. See the Intel® oneMKL Fortran Developer Reference for details.

NOTE:

Matrix Storage Schemes

Select Your Language

Using Intel.com Search

Quick Links

Recent Searches

Advanced Search

Only search in

Developer Reference for Intel® oneAPI Math Kernel Library for C

?ptsv

Syntax

Include Files

Description

Input Parameters

Output Parameters

Return Values

LAPACK 95 Interface Notes