rTensor (version 1.4)

ttm: Tensor Times Matrix (m-Mode Product)

Description

Contracted (m-Mode) product between a Tensor of arbitrary number of modes and a matrix. The result is folded back into Tensor.

Usage

ttm(tnsr, mat, m = NULL)

Arguments

tnsr

Tensor object with K modes

mat

input matrix with same number columns as the mth mode of tnsr

m

the mode to contract on

Value

a Tensor object with K modes

Details

By definition, rs_unfold(ttm(tnsr,mat),m) = mat%*%rs_unfold(tnsr,m), so the number of columns in mat must match the mth mode of tnsr. For the math on the m-Mode Product, see Kolda and Bader (2009).

References

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

See Also

ttl, rs_unfold-methods

Examples

# NOT RUN {
tnsr <- new("Tensor",3L,c(3L,4L,5L),data=runif(60))
mat <- matrix(runif(50),ncol=5)
ttm(tnsr,mat,m=3)
# }