The WFDB Toolbox for MATLAB/Octave is a collection of functions for reading, writing, and processing physiologic signals in the formats used by PhysioNet (see README for details).
visgraph.m is a wrapper for a command-line tool called visibility (previously misspelled as visbility) which was included in very old versions of the toolbox but got lost at some point. This re-adds the tool and fixes the spelling.
visgraph.mis a wrapper for a command-line tool calledvisibility(previously misspelled asvisbility) which was included in very old versions of the toolbox but got lost at some point. This re-adds the tool and fixes the spelling.