web_matrix, an Octave code which stores sample matrices describing a web page network. These matrices are typically very sparse, and the examples here are stored using the sparse triplet (ST) format. They can be used to demonstrate pagerank and other graph algorithms.
The information on this web page is distributed under the MIT license.
web_matrix is available in a MATLAB version and an Octave version and a Python version.
chebyshev_matrix, an Octave code which defines the Chebyshev differentiation matrix, by Lloyd Trefethen.
jordan_matrix, an Octave code which returns a random matrix in Jordan canonical form.
levenshtein_matrix, an Octave code which returns the Levenshtein distance matrix defined by two strings.
magic_matrix, an Octave code which computes a magic matrix, for any odd order n, such that all rows and columns have the same sum.
monopoly_matrix, an Octave code which computes the adjacency and transition matrices for the game of Monopoly.
pagerank, an Octave code which illustrates the eigenvalue (power method) and surfer (Markov chain) approaches to ranking web pages.
plasma_matrix, an Octave code which sets up a matrix associated with a problem in plasma physics.
power_method, an Octave code which carries out the power method for finding a dominant eigenvalue and its eigenvector.
risk_matrix, an Octave code which computes the transition and adjacency matrix for the game of RISK.
snakes_matrix, an Octave code which computes the transition matrix for Snakes and Ladders.
sparse_test, an Octave code which illustrates the use of sparse matrix utilities;
st, a data directory which illustrates the sparse triplet (ST) format for storing sparse matrices.
tennis_matrix, an Octave code which computes the transition matrix for a game of tennis, which has 17 distinct states.
test_matrix, an Octave code which defines test matrices for which the condition number, determinant, eigenvalues, eigenvectors, inverse, null vectors, P*L*U factorization or linear system solution are known. Examples include the Fibonacci, Hilbert, Redheffer, Vandermonde, Wathen and Wilkinson matrices.
wathen_matrix, an Octave code which compares storage schemes (full, banded, sparse triplet, sparse) and solution strategies (A\x, linpack, conjugate gradient (CG)) for linear systems involving the Wathen matrix, which can arise when solving a problem using the finite element method (FEM).
wishart_matrix, an Octave code which produces sample matrices from the Wishart or Bartlett distributions, useful for sampling random covariance matrices.