HPL_pdlange - Man Page
Compute ||A||.
Synopsis
#include "hpl.h"
double HPL_pdlange( const HPL_T_grid * GRID, const HPL_T_NORM NORM, const int M, const int N, const int NB, const double * A, const int LDA );
Description
HPL_pdlange returns the value of the one norm, or the infinity norm, or the element of largest absolute value of a distributed matrix A:
max(abs(A(i,j))) when NORM = HPL_NORM_A,
norm1(A), when NORM = HPL_NORM_1,
normI(A), when NORM = HPL_NORM_I,
where norm1 denotes the one norm of a matrix (maximum column sum) and normI denotes the infinity norm of a matrix (maximum row sum). Note that max(abs(A(i,j))) is not a matrix norm.
Arguments
- GRID (local input) const HPL_T_grid *
On entry, GRID points to the data structure containing the process grid information.
- NORM (global input) const HPL_T_NORM
On entry, NORM specifies the value to be returned by this function as described above.
- M (global input) const int
On entry, M specifies the number of rows of the matrix A. M must be at least zero.
- N (global input) const int
On entry, N specifies the number of columns of the matrix A. N must be at least zero.
- NB (global input) const int
On entry, NB specifies the blocking factor used to partition and distribute the matrix. NB must be larger than one.
- A (local input) const double *
On entry, A points to an array of dimension (LDA,LocQ(N)), that contains the local pieces of the distributed matrix A.
- LDA (local input) const int
On entry, LDA specifies the leading dimension of the array A. LDA must be at least max(1,LocP(M)).
See Also
HPL_pdlaprnt (3), HPL_fprintf (3).