collapse.m

Removes degenerate portions of a cell array tree.

%c = collapse(c)
% Takes a recursive cell array as a tree and collapses any branches
% having a fanout of 1. Any elements with fanout of 0 are removed.
%
%Examples:
% collapse({1 2 3}) --> {1 2 3}
% collapse({{1} {2} {{3}}}) --> {1 2 3}
% collapse({1 {2 3}}) --> {1 {2 3}}
% collapse({1 {{} 2 {{}} 3}}) --> {1 {2 3}}
% collapse({{{}}}) --> {}
%
% [matches] = regexp({'abc', 'def', 'fghi'}, '[^f]*f+[^f]*', 'match');
% collapse(matches) --> {'def' 'fghi'}
%