maint: Clean up m-files to follow Octave coding conventions. Try to trim long lines to < 80 chars. Use '##' for single line comments. Use '(...)' around tests for if/elseif/switch/while. Abut cell indexing operator '{' next to variable. Abut array indexing operator '(' next to variable. Use space between negation operator '!' and following expression. Use two newlines between endfunction and start of %!test or %!demo code. Remove unnecessary parens grouping between short-circuit operators. Remove stray extra spaces (typos) between variables and assignment operators. Remove stray extra spaces from ends of lines.

--- a/scripts/time/etime.m	Mon Feb 23 16:42:25 2015 +0000
+++ b/scripts/time/etime.m	Mon Feb 23 14:54:39 2015 -0800
@@ -72,7 +72,7 @@
 %! assert (etime (t4, t1), 60);
 %! assert (etime (t5, t1), 13);
 
-%% Test input validation
+## Test input validation
 %!error etime ();
 %!error etime (1);
 %!error etime (1, 2, 3);