has special sparse-array technology for efficiently handling arrays with literally astronomical numbers of elements when only a small fraction of the elements are nonzero. Mathematica
's linear algebra and all standard list operations can be done in symbolic form on SparseArray
objects, in which nonzero elements are specified by giving rules—potentially including patterns—for the values of elements at particular positions.
create a sparse array of any rank from a list of rules or a dense array
convert a sparse array to a dense array of explicit lists
find position→value rules for elements in a sparse array
convert symbolic equations to sparse arrays
visualize a 2D sparse array using grayscales or other color maps
visualize a sparse matrix with color, ticks, etc.
take a sparse array as the adjacency matrix for a graph