# HG changeset patch
# User paramaniac
# Date 1331408706 0
# Node ID 40a1e6b3672660f6d888621578fce41f940c7770
# Parent  cdf1dbf20cd46cfce8a7c8e961be271bb4638fab
control: use recursion instead of for-loop for subs ref

diff -r cdf1dbf20cd4 -r 40a1e6b36726 main/control/inst/@lti/subsref.m
--- a/main/control/inst/@lti/subsref.m	Sat Mar 10 16:03:47 2012 +0000
+++ b/main/control/inst/@lti/subsref.m	Sat Mar 10 19:45:06 2012 +0000
@@ -1,4 +1,4 @@
-## Copyright (C) 2009   Lukas F. Reichlin
+## Copyright (C) 2009, 2012   Lukas F. Reichlin
 ##
 ## This file is part of LTI Syncope.
 ##
@@ -21,37 +21,32 @@
 
 ## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
 ## Created: September 2009
-## Version: 0.2
+## Version: 0.3
 
 function a = subsref (a, s)
 
-  if (isempty (s))
-    error ("lti: subsref: missing index");
+  if (numel (s) == 0)
+    return;
   endif
 
-  for k = 1 : numel (s)
-    if (isa (a, "lti"))
-      switch (s(k).type)
-        case "()"
-          idx = s(k).subs;
-          if (numel (idx) == 2)
-            a = __sys_prune__ (a, idx{1}, idx{2});
-          elseif (numel (idx) == 1)
-            a = __freqresp__ (a, idx{1});  
-          else
-            error ("lti: subsref: need one or two indices");
-          endif
-        case "."
-          fld = s(k).subs;
-          a = get (a, fld);
-          ## warning ("lti: subsref: do not use subsref for development");
-        otherwise
-          error ("lti: subsref: invalid subscript type");
-      endswitch
-    else  # not an LTI model
-      a = subsref (a, s(k:end));
-      return;
-    endif
-  endfor
+  switch (s(1).type)
+    case "()"
+      idx = s(1).subs;
+      if (numel (idx) == 2)
+        a = __sys_prune__ (a, idx{1}, idx{2});
+      elseif (numel (idx) == 1)
+        a = __freqresp__ (a, idx{1});  
+      else
+        error ("lti: subsref: need one or two indices");
+      endif
+    case "."
+      fld = s(1).subs;
+      a = get (a, fld);
+      ## warning ("lti: subsref: do not use subsref for development");
+    otherwise
+      error ("lti: subsref: invalid subscript type");
+  endswitch
+  
+  a = subsref (a, s(2:end));
 
-endfunction
\ No newline at end of file
+endfunction