A table showing the evolutionary distances between all pairs of nucleotide sequences in a dataset.

Matrix which visualizes the calculation of the score of an optimal pairwise alignment (i.e. distance) of sequences or other attributes. Distances are small for similar sequences. The Protdist program we use computes a distance measure for protein sequences, using maximum likelihood estimates based on a particular matrix that indicates the significance of certain amino acid changes.

a matrix that lists the shortest paths between each node of the hypertext (if one exists)

The method used to present the results of the calculation of an optimal pairwise alignment score. The matrix field (i,j) is the score assigned to the optimal alignment between two residues (up to a total of i by j residues) from the input sequences. Each entry is calculated from the top-left neighboring entries by way of a recursive equation.

In mathematics, a distance matrix is a matrix (two-dimensional array) containing the distances, taken pairwise, of a set of points. It is therefore a symmetric N×N matrix containing non-negative reals as elements, given N points in Euclidean space. The number of pairs of points N×(N-1)/2 is the number of independent elements in the distance matrix.