
spbtrs.f(3) LAPACK spbtrs.f(3)
NAME
spbtrs.f 
SYNOPSIS
Functions/Subroutines
subroutine spbtrs (UPLO, N, KD, NRHS, AB, LDAB, B, LDB, INFO)
SPBTRS
Function/Subroutine Documentation
subroutine spbtrs (characterUPLO, integerN, integerKD, integerNRHS, real, dimension( ldab, *
)AB, integerLDAB, real, dimension( ldb, * )B, integerLDB, integerINFO)
SPBTRS
Purpose:
SPBTRS solves a system of linear equations A*X = B with a symmetric
positive definite band matrix A using the Cholesky factorization
A = U**T*U or A = L*L**T computed by SPBTRF.
Parameters:
UPLO
UPLO is CHARACTER*1
= 'U': Upper triangular factor stored in AB;
= 'L': Lower triangular factor stored in AB.
N
N is INTEGER
The order of the matrix A. N >= 0.
KD
KD is INTEGER
The number of superdiagonals of the matrix A if UPLO = 'U',
or the number of subdiagonals if UPLO = 'L'. KD >= 0.
NRHS
NRHS is INTEGER
The number of right hand sides, i.e., the number of columns
of the matrix B. NRHS >= 0.
AB
AB is REAL array, dimension (LDAB,N)
The triangular factor U or L from the Cholesky factorization
A = U**T*U or A = L*L**T of the band matrix A, stored in the
first KD+1 rows of the array. The jth column of U or L is
stored in the jth column of the array AB as follows:
if UPLO ='U', AB(kd+1+ij,j) = U(i,j) for max(1,jkd)<=i<=j;
if UPLO ='L', AB(1+ij,j) = L(i,j) for j<=i<=min(n,j+kd).
LDAB
LDAB is INTEGER
The leading dimension of the array AB. LDAB >= KD+1.
B
B is REAL array, dimension (LDB,NRHS)
On entry, the right hand side matrix B.
On exit, the solution matrix 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 = i, the ith argument had an illegal value
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
November 2011
Definition at line 122 of file spbtrs.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 spbtrs.f(3) 
