dpttrs.f man page

dpttrs.f

Synopsis

Functions/Subroutines

subroutine dpttrs (N, NRHS, D, E, B, LDB, INFO)
DPTTRS

Function/Subroutine Documentation

subroutine dpttrs (integer N, integer NRHS, double precision, dimension( * ) D, double precision, dimension( * ) E, double precision, dimension( ldb, * ) B, integer LDB, integer INFO)

DPTTRS  

Purpose:

 DPTTRS solves a tridiagonal system of the form
    A * X = B
 using the L*D*L**T factorization of A computed by DPTTRF.  D is a
 diagonal matrix specified in the vector D, L is a unit bidiagonal
 matrix whose subdiagonal is specified in the vector E, and X and B
 are N by NRHS matrices.
Parameters:

N

          N is INTEGER
          The order of the tridiagonal matrix A.  N >= 0.

NRHS

          NRHS is INTEGER
          The number of right hand sides, i.e., the number of columns
          of the matrix B.  NRHS >= 0.

D

          D is DOUBLE PRECISION array, dimension (N)
          The n diagonal elements of the diagonal matrix D from the
          L*D*L**T factorization of A.

E

          E is DOUBLE PRECISION array, dimension (N-1)
          The (n-1) subdiagonal elements of the unit bidiagonal factor
          L from the L*D*L**T factorization of A.  E can also be regarded
          as the superdiagonal of the unit bidiagonal factor U from the
          factorization A = U**T*D*U.

B

          B is DOUBLE PRECISION array, dimension (LDB,NRHS)
          On entry, the right hand side vectors B for the system of
          linear equations.
          On exit, the solution vectors, X.

LDB

          LDB is INTEGER
          The leading dimension of the array B.  LDB >= max(1,N).

INFO

          INFO is INTEGER
          = 0: successful exit
          < 0: if INFO = -k, the k-th argument had an illegal value
Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

December 2016

Definition at line 111 of file dpttrs.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page dpttrs(3) is an alias of dpttrs.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK