Multidimensional sparse array (3-way tensor) in R
Using the Matrix package I can create a two-dimensional sparse matrix. Can someone suggest a package that would allow me to create a multidimensional (specifically a 3-dimensional) sparse matrix (array, or technically a three-way tensor) in R? The slam package has a simple_sparse_array class: http://finzi.psych.upenn.edu/R/library/slam/html/array.html , although it only has support for indexing and coercion (if you wanted to do tensor operations, or elementwise arithmetic, without converting back to a regular dense array, you'd have to implement them yourself ...) I found this by doing library