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DSYR2KRun Method

Purpose ======= DSYR2K performs one of the symmetric rank 2k operations C := alpha*A*B' + alpha*B*A' + beta*C, or C := alpha*A'*B + alpha*B'*A + beta*C, where alpha and beta are scalars, C is an n by n symmetric matrix and A and B are n by k matrices in the first case and k by n matrices in the second case.

Namespace: DotNumerics.LinearAlgebra.CSLapack
Assembly: DWSIM.MathOps.DotNumerics (in DWSIM.MathOps.DotNumerics.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
Copy
public void Run(
	string UPLO,
	string TRANS,
	int N,
	int K,
	double ALPHA,
	double[] A,
	int offset_a,
	int LDA,
	double[] B,
	int offset_b,
	int LDB,
	double BETA,
	ref double[] C,
	int offset_c,
	int LDC
)
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Parameters

UPLO  String
- CHARACTER*1. On entry, UPLO specifies whether the upper or lower triangular part of the array C is to be referenced as follows: UPLO = 'U' or 'u' Only the upper triangular part of C is to be referenced. UPLO = 'L' or 'l' Only the lower triangular part of C is to be referenced. Unchanged on exit.
TRANS  String
- CHARACTER*1. On entry, TRANS specifies the operation to be performed as follows: TRANS = 'N' or 'n' C := alpha*A*B' + alpha*B*A' + beta*C. TRANS = 'T' or 't' C := alpha*A'*B + alpha*B'*A + beta*C. TRANS = 'C' or 'c' C := alpha*A'*B + alpha*B'*A + beta*C. Unchanged on exit.
N  Int32
- INTEGER. On entry, N specifies the order of the matrix C. N must be at least zero. Unchanged on exit.
K  Int32
- INTEGER. On entry with TRANS = 'N' or 'n', K specifies the number of columns of the matrices A and B, and on entry with TRANS = 'T' or 't' or 'C' or 'c', K specifies the number of rows of the matrices A and B. K must be at least zero. Unchanged on exit.
ALPHA  Double
- DOUBLE PRECISION. On entry, ALPHA specifies the scalar alpha. Unchanged on exit.
A  Double
- DOUBLE PRECISION array of DIMENSION ( LDA, ka ), where ka is k when TRANS = 'N' or 'n', and is n otherwise. Before entry with TRANS = 'N' or 'n', the leading n by k part of the array A must contain the matrix A, otherwise the leading k by n part of the array A must contain the matrix A. Unchanged on exit.
offset_a  Int32
 
LDA  Int32
- INTEGER. On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. When TRANS = 'N' or 'n' then LDA must be at least max( 1, n ), otherwise LDA must be at least max( 1, k ). Unchanged on exit.
B  Double
- DOUBLE PRECISION array of DIMENSION ( LDB, kb ), where kb is k when TRANS = 'N' or 'n', and is n otherwise. Before entry with TRANS = 'N' or 'n', the leading n by k part of the array B must contain the matrix B, otherwise the leading k by n part of the array B must contain the matrix B. Unchanged on exit.
offset_b  Int32
 
LDB  Int32
- INTEGER. On entry, LDB specifies the first dimension of B as declared in the calling (sub) program. When TRANS = 'N' or 'n' then LDB must be at least max( 1, n ), otherwise LDB must be at least max( 1, k ). Unchanged on exit.
BETA  Double
- DOUBLE PRECISION. On entry, BETA specifies the scalar beta. Unchanged on exit.
C  Double
:= alpha*A*B' + alpha*B*A' + beta*C,
offset_c  Int32
 
LDC  Int32
- INTEGER. On entry, LDC specifies the first dimension of C as declared in the calling (sub) program. LDC must be at least max( 1, n ). Unchanged on exit.
See Also