Computes the reciprocal pivot growth factor. More...
#include <math.h>
#include "slu_sdefs.h"
Functions | |
float | sPivotGrowth (int ncols, SuperMatrix *A, int *perm_c, SuperMatrix *L, SuperMatrix *U) |
Computes the reciprocal pivot growth factor.
-- SuperLU routine (version 2.0) -- Univ. of California Berkeley, Xerox Palo Alto Research Center, and Lawrence Berkeley National Lab. November 15, 1997
float sPivotGrowth | ( | int | ncols, | |
SuperMatrix * | A, | |||
int * | perm_c, | |||
SuperMatrix * | L, | |||
SuperMatrix * | U | |||
) |
Purpose =======
Compute the reciprocal pivot growth factor of the leading ncols columns of the matrix, using the formula: min_j ( max_i(abs(A_ij)) / max_i(abs(U_ij)) )
Arguments =========
ncols (input) int The number of columns of matrices A, L and U.
A (input) SuperMatrix* Original matrix A, permuted by columns, of dimension (A->nrow, A->ncol). The type of A can be: Stype = NC; Dtype = SLU_S; Mtype = GE.
L (output) SuperMatrix* The factor L from the factorization Pr*A=L*U; use compressed row subscripts storage for supernodes, i.e., L has type: Stype = SC; Dtype = SLU_S; Mtype = TRLU.
U (output) SuperMatrix* The factor U from the factorization Pr*A*Pc=L*U. Use column-wise storage scheme, i.e., U has types: Stype = NC; Dtype = SLU_S; Mtype = TRU.