unmatvec: Unmatvec Folding of 2D DelayedArray

In rikenbit/DelayedTensor: R package for sparse and out-of-core arithmetic and decomposition of Tensor

Unmatvec Folding of 2D DelayedArray

Description

The inverse operation to matvec-methods, turning a matrix into a Tensor. For a full account of matrix folding/unfolding operations, consult Kolda and Bader (2009).

Usage

unmatvec(mat, modes = NULL)

## S4 method for signature 'DelayedArray'
unmatvec(mat, modes)

Arguments

mat	DelayedArray object (only 2D)
modes	the modes of the output DelayedArray

Details

This function is an extension of the unmatvec by DelayedArray.

This is a wrapper function to fold.

Value

DelayedArray object with modes given by modes

References

T. Kolda, B. Bader, "Tensor decomposition and applications". SIAM Applied Mathematics and Applications 2009.

See Also

fold, matvec

Examples

library("DelayedRandomArray")
darr <- RandomUnifArray(c(2,3,4))
matT1 <- matvec(darr)
identical(
    as.array(unmatvec(matT1, modes=c(2,3,4))),
    as.array(darr))

rikenbit/DelayedTensor documentation built on Jan. 30, 2023, 6:15 p.m.