cgttrs.f man page

cgttrs.f

Synopsis

Functions/Subroutines

subroutine cgttrs (TRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB, INFO)
CGTTRS

Function/Subroutine Documentation

subroutine cgttrs (character TRANS, integer N, integer NRHS, complex, dimension( * ) DL, complex, dimension( * ) D, complex, dimension( * ) DU, complex, dimension( * ) DU2, integer, dimension( * ) IPIV, complex, dimension( ldb, * ) B, integer LDB, integer INFO)

CGTTRS  

Purpose:

 CGTTRS solves one of the systems of equations
    A * X = B,  A**T * X = B,  or  A**H * X = B,
 with a tridiagonal matrix A using the LU factorization computed
 by CGTTRF.
Parameters:

TRANS

          TRANS is CHARACTER*1
          Specifies the form of the system of equations.
          = 'N':  A * X = B     (No transpose)
          = 'T':  A**T * X = B  (Transpose)
          = 'C':  A**H * X = B  (Conjugate transpose)

N

          N is INTEGER
          The order of the matrix A.

NRHS

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

DL

          DL is COMPLEX array, dimension (N-1)
          The (n-1) multipliers that define the matrix L from the
          LU factorization of A.

D

          D is COMPLEX array, dimension (N)
          The n diagonal elements of the upper triangular matrix U from
          the LU factorization of A.

DU

          DU is COMPLEX array, dimension (N-1)
          The (n-1) elements of the first super-diagonal of U.

DU2

          DU2 is COMPLEX array, dimension (N-2)
          The (n-2) elements of the second super-diagonal of U.

IPIV

          IPIV is INTEGER array, dimension (N)
          The pivot indices; for 1 <= i <= n, row i of the matrix was
          interchanged with row IPIV(i).  IPIV(i) will always be either
          i or i+1; IPIV(i) = i indicates a row interchange was not
          required.

B

          B is COMPLEX array, dimension (LDB,NRHS)
          On entry, the matrix of right hand side vectors B.
          On exit, B is overwritten by 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 140 of file cgttrs.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

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

Tue Nov 14 2017 Version 3.8.0 LAPACK