[Scipy-svn] r3954 - trunk/scipy/stats/models

[scipy-svn@scip...]

Author: jonathan.taylor
Date: 2008-02-22 13:48:39 -0600 (Fri, 22 Feb 2008)
New Revision: 3954

Modified:
   trunk/scipy/stats/models/formula.py
Log:
allowed reference key for main_effect to be a key or an int

Modified: trunk/scipy/stats/models/formula.py
===================================================================
--- trunk/scipy/stats/models/formula.py	2008-02-21 18:26:04 UTC (rev 3953)
+++ trunk/scipy/stats/models/formula.py	2008-02-22 19:48:39 UTC (rev 3954)
@@ -256,14 +256,24 @@
     def main_effect(self, reference=None):
         """
         Return the 'main effect' columns of a factor, choosing
-        a reference column number to remove.
+        an optional reference key. 
+
+	The reference key can be one of the keys of the Factor,
+        or an integer, representing which column to remove.
+        It defaults to 0.
+        
         """
 
+        names = self.names()
+
         if reference is None:
             reference = 0
+        else:
+            try:
+                reference = names.index(reference)
+            except IndexError:
+                reference = int(reference)
 
-        names = self.names()
-
         def maineffect_func(value, reference=reference):
             rvalue = []
             keep = range(value.shape[0])