magic4_matrix, an Octave code which computes an nxn magic matrix, where n is a multiple of 4, such that all rows, columns, the diagonal and antidiagonal have the same sum.
In general, a magic matrix is an n by n array, whose entries include each positive integer from 1 to n^2, in such a way that each row and column has a common sum. Sometimes the diagonals also form this sum.
This code handles the case where the matrix order n is a multiple of 4.
The information on this web page is distributed under the MIT license.
magic4_matrix is available in a MATLAB version and an Octave version and a Python version.
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, columns, the diagonal and antidiagonal have the same sum.
monopoly_matrix, an Octave code which computes the adjacency and transition matrices for the game of Monopoly.
plasma_matrix, an Octave code which sets up a matrix associated with a problem in plasma physics.
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 the game of Snakes and Ladders.
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.
usa_matrix, an Octave code which defines the adjacency matrix for US states, using a variety of matrix formats.
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).
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