---
name: "pspttrs"
section: "3"
platform: "linux"
package: "scalapack-doc"
version: "1.5-11"
release: "Debian 11 (Bullseye)"
platforms: ["linux"]
url: "https://new.carta.tech/pspttrs"
---

# pspttrs(3)

solve a system of linear equations A(1:N, JA:JA+N-1) \* X = B(IB:IB+N-1, 1:NRHS)

## NAME

PSPTTRS - solve a system of linear equations   A(1:N, JA:JA+N-1) \* X = B(IB:IB+N-1, 1:NRHS)

## SYNOPSIS

- SUBROUTINE PSPTTRS(

  N, NRHS, D, E, JA, DESCA, B, IB, DESCB, AF, LAF, WORK, LWORK, INFO )

- INTEGER

  IB, INFO, JA, LAF, LWORK, N, NRHS

- INTEGER

  DESCA( \* ), DESCB( \* )

- REAL

  AF( \* ), B( \* ), D( \* ), E( \* ), WORK( \* )

## PURPOSE

PSPTTRS solves a system of linear equations

where A(1:N, JA:JA+N-1) is the matrix used to produce the factors stored in A(1:N,JA:JA+N-1) and AF by PSPTTRF.\
 A(1:N, JA:JA+N-1) is an N-by-N real\
 tridiagonal symmetric positive definite distributed\
 matrix.\

Routine PSPTTRF MUST be called first.\