X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo%2Fsymbol_sequence.py;h=2a104aed958d877103e1962f1ad212e2ab07c981;hb=1bbade9f41ffbfe366b15d0db657f666bc1f025d;hp=2abf41b786f709afa8581c8509fd4ee6944ae0a4;hpb=9a5d67ab5b0e8bf6515061486ce41042c89b9dac;p=sage.d.git

diff --git a/mjo/symbol_sequence.py b/mjo/symbol_sequence.py
index 2abf41b..2a104ae 100644
--- a/mjo/symbol_sequence.py
+++ b/mjo/symbol_sequence.py
@@ -1,7 +1,7 @@
 from sage.all import *
 
 class SymbolSequence:
-    """
+    r"""
     An iterable object which acts like a sequence of symbolic
     expressions (variables).
 
@@ -38,13 +38,13 @@ class SymbolSequence:
     degree::
 
         sage: a = SymbolSequence('a')
-        sage: p = sum( a[i]*x^i for i in xrange(5) )
+        sage: p = sum( a[i]*x^i for i in range(5) )
         sage: p
         a_4*x^4 + a_3*x^3 + a_2*x^2 + a_1*x + a_0
 
     Using a different latex name since 'lambda' is reserved::
 
-        sage: l = SymbolSequence('l', '\lambda')
+        sage: l = SymbolSequence('l', r'\lambda')
         sage: l[0]
         l_0
         sage: latex(l[0])
@@ -57,7 +57,7 @@ class SymbolSequence:
         a_0_1_2
         sage: latex(a[0,1,2])
         a_{0}_{1}_{2}
-        sage: [ a[i,j] for i in xrange(2) for j in xrange(2) ]
+        sage: [ a[i,j] for i in range(2) for j in range(2) ]
         [a_0_0, a_0_1, a_1_0, a_1_1]
 
     You can pass slices instead of integers to obtain a list of
@@ -175,9 +175,10 @@ class SymbolSequence:
         result = []
 
         for item in l:
-            if isinstance(item, list):
+            try:
+                item = iter(item)
                 result += self._flatten_list_(item)
-            else:
+            except TypeError:
                 result += [item]
 
         return result
@@ -283,7 +284,7 @@ class SymbolSequence:
         # If the user asks for a slice, we'll be returning a list
         # of symbols.
         return [ self._subscript_integer_(idx)
-                 for idx in xrange(start, s.stop, step) ]
+                 for idx in range(start, s.stop, step) ]
 
 
 
@@ -332,7 +333,7 @@ class SymbolSequence:
                    for w in v )
 
             # This might be nested...
-            maybe_nested_list = [ s._subscript_tuple_(args) for s in ss ]
+            maybe_nested_list = ( s._subscript_tuple_(args) for s in ss )
             return self._flatten_list_(maybe_nested_list)
 
         else: