MeatAxe: ztm - Tensor Multiply

MeatAxe 2.4

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ztm - Tensor Multiply

## Command Line

    ztm [Options] A B Vectors Result

Options
  Standard options, see Standard Command Line Options.

-s Start
  Start with the given seed vector number instead of 1.

A
  Input file: Left factor (square matrix).

B
  Input file: Right factor (square matrix).

Vectors
  Input file: Vectors to be multiplied.

Result
  Output file: Vectors.

## Input Files

A
  Left factor, m×m matrix.

B
  Right factor, n×n matrix.

Vectors
  Vectors to be multiplied, a r×(mn) matrix.

## Output Files

Result
  Vectors.

## Description

This program reads two matrices from A and B, a list of vectors, and calculates the image of the vectors under A⊗B. A and B must be square matrices of dimension m and n, respetively This calculation could be done with the zte and zmu programs, but using ztm avoids the memory-consuming calculation of A⊗B.

### Implementation Details

Let m, n be the dimensions of A and B, respectively. For each input vector v∊F1×mn, the program computes the m×n matrix with

Then, v(A⊗B) can be computed by ordinary matrix operations:

Both matrices and one vector must fit into memory at the same time.