MatMatTransposeMult#

Performs matrix-matrix multiplication \(C = A*B^T\).

Synopsis#

#include "petscmat.h" 
PetscErrorCode MatMatTransposeMult(Mat A, Mat B, MatReuse scall, PetscReal fill, Mat *C)

Neighbor-wise Collective

Input Parameters#

Output Parameter#

  • C - the product matrix

Options Database Key#

  • -matmattransmult_mpidense_mpidense_via {allgatherv,cyclic} - Choose between algorithms for MATMPIDENSE matrices: the first redundantly copies the transposed B matrix on each process and requires O(log P) communication complexity; the second never stores more than one portion of the B matrix at a time but requires O(P) communication complexity.

Notes#

C will be created if MAT_INITIAL_MATRIX and must be destroyed by the user with MatDestroy().

MAT_REUSE_MATRIX can only be used if the matrices A and B have the same nonzero pattern as in the previous call

To determine the correct fill value, run with -info and search for the string “Fill ratio” to see the value actually needed.

This routine is currently only implemented for pairs of MATSEQAIJ matrices, for the MATSEQDENSE class, and for pairs of MATMPIDENSE matrices.

This routine is shorthand for using MatProductCreate() with the MatProductType of MATPRODUCT_ABt

The deprecated PETSC_DEFAULT in fill also means use the current value

See Also#

Matrices, Mat, MatProductCreate(), MATPRODUCT_ABt, MatMatMult(), MatTransposeMatMult() MatPtAP(), MatProductAlgorithm, MatProductType

Level#

intermediate

Location#

src/mat/interface/matrix.c


Index of all Mat routines
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Index of all manual pages