X-Git-Url: https://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo%2Fcone%2Fpermutation_invariant.py;h=d0715867a35770470cb47c384d3b84656d012a2c;hb=928b7d49fda98ff105c92293b5797bb7a2b9873a;hp=d87ace2be9a034264b497586130bc6a3492e9be2;hpb=268dadd157251fdf78924324bbf6d7dabefb76f2;p=sage.d.git

diff --git a/mjo/cone/permutation_invariant.py b/mjo/cone/permutation_invariant.py
index d87ace2..d071586 100644
--- a/mjo/cone/permutation_invariant.py
+++ b/mjo/cone/permutation_invariant.py
@@ -50,16 +50,25 @@ def is_permutation_invariant(K):
 
     SETUP::
 
-        sage: from mjo.cone.rearrangement import rearrangement_cone
+        sage: from mjo.cone.nonnegative_orthant import nonnegative_orthant
         sage: from mjo.cone.permutation_invariant import is_permutation_invariant
+        sage: from mjo.cone.rearrangement import rearrangement_cone
+
+    EXAMPLES:
 
-    EXAMPLES::
+    The rearrangement cone is permutation-invariant::
 
         sage: all( is_permutation_invariant(rearrangement_cone(p,n))
         ....:               for n in range(3, 6)
         ....:               for p in range(1, n) )
         True
 
+    As is the nonnegative orthant::
+
+        sage: K = nonnegative_orthant(ZZ.random_element(5))
+        sage: is_permutation_invariant(K)
+        True
+
     """
     # We'll need this to turn rays into vectors so that we can permute
     # them with permutation matrices.