help metricp

Title

metricp -- Test a symmetric matrix of pairwise distances for the triangle inequality

Syntax

metricp matname [,countlimit(int) detailed]

Options

Count limit
countlimit(int) Number of triangle-inequality infringements to report (defaults to 10, 0 means no limit)

detailed Slowly identify the problem cases, not just the fact they exist.

Description

metricp takes a matrix of pairwise distances and tests that
the triangle inequality is observed. If it finds triads infringing on
the inequality it reports at most 10 before stopping (this is changed
with the option countlimit; set that to zero for no limit). If
there are no infringing cases and the matrix is large, it can be a
little slow (tens of seconds). It is even slower with the detailed
option (minutes), which identifies the infringing trio of sequences;
without this option only the fact that there is a shorter route between
sequence i and sequence j is reported.

Author

Brendan Halpin, brendan.halpin@ul.ie

Examples

. metricp pwd

Version