renamed the iterator '_reverse' to 'arg_iterator' for clarity
---
sympy/physics/secondquant.py | 23 ++++++++++-------------
1 files changed, 10 insertions(+), 13 deletions(-)
diff --git a/sympy/physics/secondquant.py b/sympy/physics/secondquant.py
index b7ae493..93f9ca3 100644
--- a/sympy/physics/secondquant.py
+++ b/sympy/physics/secondquant.py
@@ -2417,11 +2417,9 @@ def evaluate_deltas(e):
else:
return e
-def _get_dummies(expr, _reverse, **require):
+def _get_dummies(expr, arg_iterator, **require):
"""
- Collects dummies recursively in predictable order.
-
- Starting at right end to prioritize indices of non-commuting terms.
+ Collects dummies recursively in predictable order as defined by
arg_iterator.
FIXME: A more sophisticated predictable order would work better.
Current implementation does not always work if factors commute. Since
@@ -2431,7 +2429,7 @@ def _get_dummies(expr, _reverse, **require):
"""
result = []
- for arg in _reverse(expr.args):
+ for arg in arg_iterator(expr.args):
try:
if arg.dummy_index:
# here we check that the dummy matches requirements
@@ -2443,7 +2441,7 @@ def _get_dummies(expr, _reverse, **require):
except AttributeError:
try:
if arg.args:
- result.extend(_get_dummies(arg, _reverse, **require))
+ result.extend(_get_dummies(arg, arg_iterator, **require))
except AttributeError:
pass
return result
@@ -2496,9 +2494,9 @@ def _get_subslist(chaos,order):
return subslist
-def _substitute(expr, ordered_dummies, _reverse, **require):
+def _substitute(expr, ordered_dummies, arg_iterator, **require):
"""
- Substitute dummies in expr (which should be a Mul object)
+ Substitute dummies in expr
If keyword arguments are given, those dummies that have an identical
keyword in .assumptions0 must provide the same value (True or False)
@@ -2525,8 +2523,7 @@ def _substitute(expr, ordered_dummies, _reverse,
**require):
"""
- dummies = _remove_duplicates(_get_dummies(expr, _reverse, **require))
-
+ dummies = _remove_duplicates(_get_dummies(expr, arg_iterator, **require))
subslist = _get_subslist(dummies, ordered_dummies)
result = expr.subs(subslist)
@@ -2603,13 +2600,13 @@ def _p(number):
# reverse iterator for use in _get_dummies()
if reverse_order:
- def _reverse(seq):
+ def arg_iterator(seq):
i=len(seq)
while i>0:
i += -1
yield seq[i]
else:
- def _reverse(seq):
+ def arg_iterator(seq):
for i in xrange(len(seq)):
yield seq[i]
@@ -2659,7 +2656,7 @@ def _reverse(seq):
for req, dummylist in cases:
if isinstance(expr,Add):
new_dummies = dummylist
- expr = (Add(*[_substitute(term, new_dummies, _reverse, **req) for
term in expr.args]))
+ expr = (Add(*[_substitute(term, new_dummies, arg_iterator, **req)
for term in expr.args]))
return expr
--
1.6.5
--
You received this message because you are subscribed to the Google Groups
"sympy-patches" group.
To post to this group, send email to sympy-patc...@googlegroups.com.
To unsubscribe from this group, send email to
sympy-patches+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/sympy-patches?hl=en.
