FunctionLAPACKdsyrk

23. Aug. 2022

Library "FunctionLAPACKdsyrk"
subroutine part of LAPACK: Linear Algebra Package,
performs one of the symmetric rank k operations
.
C := alpha*A*A**T + beta*C, or C := alpha*A**T*A + beta*C,
.
where alpha and beta are scalars, C is an n by n symmetric matrix
and A is an n by k matrix in the first case and a k by n matrix
in the second case.
.
reference:
netlib.org/lapack/explore-html/dc/d05/dsyrk_8f_source.html

dsyrk(uplo, trans, n, k, alpha, a, lda, beta, c, ldc)
  performs one of the symmetric rank k operations
.
C := alpha*A*A**T + beta*C, or C := alpha*A**T*A + beta*C,
.
where alpha and beta are scalars, C is an n by n symmetric matrix
and A is an n by k matrix in the first case and a k by n matrix
in the second case.
.
  Parameters:
    uplo: string 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.
.
    trans: string specifies the operation to be performed as follows:
TRANS = 'N' or 'n' C := alpha*A*A**T + beta*C.
TRANS = 'T' or 't' C := alpha*A**T*A + beta*C.
TRANS = 'C' or 'c' C := alpha*A**T*A + beta*C.
.
    n: int specifies the order of the matrix C. N must be at least zero.
    k: int On entry with:
TRANS = 'N' or 'n', K specifies the number of columns of the matrix A.
TRANS = 'T' or 't' or 'C' or 'c', K specifies the number of rows of the matrix A.
K must be at least zero.
.
    alpha: float scalar.
    a: matrix<float> matrix A.
    lda: int specifies the first dimension of A.
    beta: float scalar.
    c: matrix<float> matrix C, is overwritten by the lower triangular part of the updated matrix.
    ldc: int specifies the first dimension of C
  Returns: void, C is overwritten by the lower triangular part of the updated matrix.