This package is centered around the Tensor-class
, which defines a S4 class for tensors of arbitrary number of modes. A vignette and/or a possible paper will be included in a future release of this package.
This page will summarize the full functionality of this package. Note that since all the methods associated with S4 class Tensor-class
are documented there, we will not duplicate it here.
The remaining functions can be split into two groups: the first is a set of tensor decompositions, and the second is a set of helper functions that are useful in tensor manipulation.
rTensor implements the following tensor decompositions:
cp
Canonical Polyadic (CP) decomposition
tucker
General Tucker decomposition
mpca
Multilinear Principal Component Analysis; note that for 3-Tensors this is also known as Generalized Low Rank Approximation of Matrices(GLRAM)
hosvd
(Truncated-)Higher-order singular value decomposition
t_svd
Tensor singular value decomposition; 3-Tensors only; also note that there is an asociated reconstruction function t_svd_reconstruct
pvd
Population value decomposition of images; 3-Tensors only
rTensor also provides a set functions for tensors multiplication:
ttm
Tensor times matrix, aka m-mode product
ttl
Tensor times list (of matrices)
t_mult
Tensor product based on block circulant unfolding; only implemented for a pair of 3-Tensors
...as well as for matrices:
hadamard_list
Computes the Hadamard (element-wise) product of a list of matrices
kronecker_list
Computes the Kronecker product of a list of matrices
khatri_rao
Computes the Khatri-Rao product of two matrices
khatri_rao_list
Computes the Khatri-Rao product of a list of matrices
fold
General folding of a matrix into a tensor
k_fold
Inverse operation for k_unfold
unmatvec
Inverse operation for matvec
For more information on any of the functions, please consult the individual man pages.