--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/subsSymfun.m	Fri Sep 07 14:40:58 2018 +0200
@@ -0,0 +1,14 @@
+% Subs for a symfun
+% f remains a symbolic function. If any of it's arguments is eliminated
+% it is removed from the argument list while preserving the order of the
+% other arguments
+function f = subsSymfun(f, old, new)
+    args = argnames(f);
+
+    newExpr = subs(f, old, new);
+    vars = symvar(subs(args, old, new));
+
+    newArgs = args(ismember(args,vars));
+
+    f = symfun(newExpr, newArgs);
+end
\ No newline at end of file