zpttrs
zpttrs - solve a tridiagonal system of the form A * X = B using the factorization A = U'*D*U or A = L*D*L' computed by CPTTRF
SUBROUTINE ZPTTRS( UPLO, N, NRHS, DIAG, OFFD, B, LDB, INFO)
CHARACTER * 1 UPLO
DOUBLE COMPLEX OFFD(*), B(LDB,*)
INTEGER N, NRHS, LDB, INFO
DOUBLE PRECISION DIAG(*)
SUBROUTINE ZPTTRS_64( UPLO, N, NRHS, DIAG, OFFD, B, LDB, INFO)
CHARACTER * 1 UPLO
DOUBLE COMPLEX OFFD(*), B(LDB,*)
INTEGER*8 N, NRHS, LDB, INFO
DOUBLE PRECISION DIAG(*)
SUBROUTINE PTTRS( UPLO, [N], [NRHS], DIAG, OFFD, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
COMPLEX(8), DIMENSION(:) :: OFFD
COMPLEX(8), DIMENSION(:,:) :: B
INTEGER :: N, NRHS, LDB, INFO
REAL(8), DIMENSION(:) :: DIAG
SUBROUTINE PTTRS_64( UPLO, [N], [NRHS], DIAG, OFFD, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
COMPLEX(8), DIMENSION(:) :: OFFD
COMPLEX(8), DIMENSION(:,:) :: B
INTEGER(8) :: N, NRHS, LDB, INFO
REAL(8), DIMENSION(:) :: DIAG
#include <sunperf.h>
void zpttrs(char uplo, int n, int nrhs, double *diag, doublecomplex *offd, doublecomplex *b, int ldb, int *info);
void zpttrs_64(char uplo, long n, long nrhs, double *diag, doublecomplex *offd, doublecomplex *b, long ldb, long *info);
zpttrs solves a tridiagonal system of the form
A * X = B
using the factorization A = U'*D*U or A = L*D*L' computed by CPTTRF.
D is a diagonal matrix specified in the vector D, U (or L) is a unit
bidiagonal matrix whose superdiagonal (subdiagonal) is specified in
the vector E, and X and B are N by NRHS matrices.
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* UPLO (input)
-
Specifies the form of the factorization and whether the
vector OFFD is the superdiagonal of the upper bidiagonal factor
U or the subdiagonal of the lower bidiagonal factor L.
-
* N (input)
-
The order of the tridiagonal matrix A. N >= 0.
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* NRHS (input)
-
The number of right hand sides, i.e., the number of columns
of the matrix B. NRHS >= 0.
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* DIAG (input)
-
The n diagonal elements of the diagonal matrix DIAG from the
factorization A = U'*DIAG*U or A = L*DIAG*L'.
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* OFFD (input/output)
-
If UPLO = 'U', the (n-1) superdiagonal elements of the unit
bidiagonal factor U from the factorization A = U'*DIAG*U.
If UPLO = 'L', the (n-1) subdiagonal elements of the unit
bidiagonal factor L from the factorization A = L*DIAG*L'.
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* B (input/output)
-
On entry, the right hand side vectors B for the system of
linear equations.
On exit, the solution vectors, X.
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* LDB (input)
-
The leading dimension of the array B. LDB >= max(1,N).
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* INFO (output)
-