diff general/funutils/fold.m @ 4:e44f49929e56

Adding reorganised general toolbox, now in several subdirectories.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/general/funutils/fold.m	Sat Jan 12 19:21:22 2013 +0000
@@ -0,0 +1,13 @@
+function X=fold(fn,args)
+% fold - Fold combinator from functional programming
+%
+% This function applies an associative operator to a list of arguments,
+% as if the list was written out with the operator between consecutive
+% elements, eg fold(@plus,{1,2,3,4}) = 1+2+3+4.
+%
+% fold :: 
+%    (X,X->X)	~'associative binary operator',
+%    {[N]->X} ~'list (cell array) of arguments (at least 2 elements)'
+% -> X.
+
+if isempty(args), X=[]; else X=foldl(fn,args{1},args(2:end)); end