Merge pull request #153 from sympy/python-2-modernize

Modernize Python 2 code for migration to Python 3

Author: aktech

app/__init__.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 import sys
 import os.path
 

app/logic/diffsteps.py

@@ -1,12 +1,17 @@
+from __future__ import absolute_import
 import sympy
 import collections
 
-import stepprinter
-from stepprinter import functionnames, replace_u_var
+from . import stepprinter
+from .stepprinter import functionnames, replace_u_var
 
 from sympy.core.function import AppliedUndef
 from sympy.functions.elementary.trigonometric import TrigonometricFunction
 from sympy.strategies.core import switch, identity
+from six.moves import map
+from six.moves import range
+from six.moves import zip
+from functools import reduce
 def Rule(name, props=""):
     return collections.namedtuple(name, props + " context symbol")
 
@@ -219,7 +224,7 @@ def eval_default(*args):
 
 @evaluates(MulRule)
 def eval_mul(terms, substeps, expr, symbol):
-    diffs = map(diff, substeps)
+    diffs = list(map(diff, substeps))
 
     result = sympy.S.Zero
     for i in range(len(terms)):
@@ -347,9 +352,8 @@ def print_Mul(self, rule):
             self.append("Apply the product rule:".format(
                 self.format_math(rule.context)))
 
-            fnames = map(lambda n: sympy.Function(n)(rule.symbol),
-                         functionnames(len(rule.terms)))
-            derivatives = map(lambda f: sympy.Derivative(f, rule.symbol), fnames)
+            fnames = [sympy.Function(n)(rule.symbol) for n in functionnames(len(rule.terms))]
+            derivatives = [sympy.Derivative(f, rule.symbol) for f in fnames]
             ruleform = []
             for index in range(len(rule.terms)):
                 buf = []

app/logic/intsteps.py

@@ -1,8 +1,9 @@
+from __future__ import absolute_import
 import sympy
 import collections
 from contextlib import contextmanager
-import stepprinter
-from stepprinter import functionnames, Rule, replace_u_var
+from . import stepprinter
+from .stepprinter import functionnames, Rule, replace_u_var
 
 from sympy.integrals.manualintegrate import (
     manualintegrate, _manualintegrate, integral_steps, evaluates,
@@ -40,7 +41,7 @@ def contains_dont_know(rule):
 
 def filter_unknown_alternatives(rule):
     if isinstance(rule, AlternativeRule):
-        alternatives = list(filter(lambda r: not contains_dont_know(r), rule.alternatives))
+        alternatives = list([r for r in rule.alternatives if not contains_dont_know(r)])
         if not alternatives:
             alternatives = rule.alternatives
         return AlternativeRule(alternatives, rule.context, rule.symbol)
@@ -157,7 +158,7 @@ def print_Parts(self, rule):
         with self.new_step():
             self.append("Use integration by parts:")
 
-            u, v, du, dv = map(lambda f: sympy.Function(f)(rule.symbol), 'u v du dv'.split())
+            u, v, du, dv = [sympy.Function(f)(rule.symbol) for f in 'u v du dv'.split()]
             self.append(self.format_math_display(
                 r"""\int \operatorname{u} \operatorname{dv}
                 = \operatorname{u}\operatorname{v} -
@@ -185,7 +186,7 @@ def print_CyclicParts(self, rule):
             self.append("Use integration by parts, noting that the integrand"
                         " eventually repeats itself.")
 
-            u, v, du, dv = map(lambda f: sympy.Function(f)(rule.symbol), 'u v du dv'.split())
+            u, v, du, dv = [sympy.Function(f)(rule.symbol) for f in 'u v du dv'.split()]
             current_integrand = rule.context
             total_result = sympy.S.Zero
             with self.new_level():

app/logic/logic.py

@@ -1,17 +1,19 @@
+from __future__ import absolute_import
 import sys
 import traceback
 import collections
-from utils import Eval, latexify, arguments, removeSymPy, \
+from .utils import Eval, latexify, arguments, removeSymPy, \
     custom_implicit_transformation, synonyms, OTHER_SYMPY_FUNCTIONS, \
     close_matches
-from resultsets import find_result_set, get_card, format_by_type, \
+from .resultsets import find_result_set, get_card, format_by_type, \
     is_function_handled, find_learn_more_set
 from sympy import latex, series, sympify, solve, Derivative, \
     Integral, Symbol, diff, integrate
 import sympy
 from sympy.core.function import FunctionClass
 from sympy.parsing.sympy_parser import stringify_expr, eval_expr, \
     standard_transformations, convert_xor, TokenError
+from six.moves import map
 
 PREEXEC = """from __future__ import division
 from sympy import *
@@ -115,7 +117,7 @@ def disambiguate(self, arguments):
 
     def eval_input(self, s):
         namespace = {}
-        exec PREEXEC in {}, namespace
+        exec(PREEXEC, {}, namespace)
 
         def plot(f=None, **kwargs):
             """Plot functions. Not the same as SymPy's plot.
@@ -222,7 +224,7 @@ def prepare_cards(self, parsed, arguments, evaluator, evaluated):
             if any(get_card(c).is_multivariate() for c in cards):
                 result[-1].update({
                     "num_variables": len(components['variables']),
-                    "variables": map(repr, components['variables']),
+                    "variables": list(map(repr, components['variables'])),
                     "variable": repr(components['variable'])
                 })
 

app/logic/nlcommand.py

@@ -28,7 +28,7 @@ def extraneous(word):
     return (word in prepositions) or (word in pronouns) or (word in articles)
 
 def interpret(command):
-    words = filter(lambda word: not extraneous(word), command.lower().split())
+    words = [word for word in command.lower().split() if not extraneous(word)]
     modifier = 'default'
     modifier_priority = -1
     cmds = []

app/logic/resultsets.py

@@ -1,12 +1,16 @@
+from __future__ import absolute_import
 import sys
 import json
 import itertools
 import sympy
 from sympy.core.function import FunctionClass
 from sympy.core.symbol import Symbol
 import docutils.core
-import diffsteps
-import intsteps
+from . import diffsteps
+from . import intsteps
+import six
+from six.moves import map
+from six.moves import zip
 
 
 class ResultCard(object):
@@ -383,12 +387,12 @@ def _format_dict(dictionary, formatter):
                 '<thead><tr><th>{}</th><th>{}</th></tr></thead>'.format(*title),
                 '<tbody>']
         try:
-            fdict = dictionary.iteritems()
+            fdict = six.iteritems(dictionary)
             if not any(isinstance(i,Symbol) for i in dictionary.keys()):
-                fdict = sorted(dictionary.iteritems())
+                fdict = sorted(six.iteritems(dictionary))
             for key, val in fdict:
                 html.append('<tr><td>{}</td><td>{}</td></tr>'.format(key, val))
-        except AttributeError, TypeError:  # not iterable/not a dict
+        except AttributeError as TypeError:  # not iterable/not a dict
             return formatter(dictionary)
         html.append('</tbody></table>')
         return '\n'.join(html)
@@ -654,14 +658,14 @@ def trim(docstring):
     # and split into a list of lines:
     lines = docstring.expandtabs().splitlines()
     # Determine minimum indentation (first line doesn't count):
-    indent = sys.maxint
+    indent = sys.maxsize
     for line in lines[1:]:
         stripped = line.lstrip()
         if stripped:
             indent = min(indent, len(line) - len(stripped))
     # Remove indentation (first line is special):
     trimmed = [lines[0].strip()]
-    if indent < sys.maxint:
+    if indent < sys.maxsize:
         for line in lines[1:]:
             trimmed.append(line[indent:].rstrip())
     # Strip off trailing and leading blank lines:
@@ -683,7 +687,7 @@ def eval_truth_table(evaluator, components, parameters=None):
 
     result = []
     for combination in itertools.product([True, False], repeat=len(variables)):
-        result.append(combination +(expr.subs(zip(variables, combination)),))
+        result.append(combination +(expr.subs(list(zip(variables, combination))),))
     return variables, result
 
 

app/logic/stepprinter.py

@@ -1,8 +1,11 @@
+from __future__ import absolute_import
 import sympy
 import collections
 from contextlib import contextmanager
 
 from sympy import latex
+import six
+from six.moves import range
 
 def Rule(name, props=""):
     # GOTCHA: namedtuple class name not considered!
@@ -94,7 +97,7 @@ def format_math(self, math):
             latex(math))
 
     def format_math_display(self, math):
-        if not isinstance(math, basestring):
+        if not isinstance(math, six.string_types):
             math = latex(math)
         return '<script type="math/tex; mode=display">{}</script>'.format(
             math)

app/logic/utils.py

@@ -1,4 +1,5 @@
 from __future__ import division
+from __future__ import absolute_import
 import difflib
 import collections
 import traceback
@@ -11,6 +12,8 @@
 from sympy.core.relational import Relational
 import sympy.parsing.sympy_tokenize as sympy_tokenize
 from token import NAME
+from six.moves import map
+from six.moves import zip
 
 OTHER_SYMPY_FUNCTIONS = ('sqrt',)
 
@@ -236,7 +239,7 @@ def format_diophantine(node, visitor):
         klass = sympy.Sum
     else:
         klass = sympy.Product
-    return sympy.latex(klass(*map(visitor.evaluator.eval_node, node.args)))
+    return sympy.latex(klass(*list(map(visitor.evaluator.eval_node, node.args))))
 
 @LatexVisitor.formats_function('help')
 def format_help(node, visitor):

app/models.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 import six
 import os
 # https://github.com/googleapis/python-ndb/issues/249#issuecomment-560957294

app/templatetags/extra_tags.py

@@ -1,5 +1,7 @@
+from __future__ import absolute_import
 from django import template
-import urllib
+import six.moves.urllib.request, six.moves.urllib.parse, six.moves.urllib.error
+import six
 register = template.Library()
 
 @register.inclusion_tag('card.html')
@@ -24,10 +26,10 @@ def __init__(self, query):
             self.query = template.Variable(query)
 
     def render(self, context):
-        if isinstance(self.query, unicode):
-            return "/input/?i=" + urllib.quote(self.query[1:-1])
+        if isinstance(self.query, six.text_type):
+            return "/input/?i=" + six.moves.urllib.parse.quote(self.query[1:-1])
         else:
-            return "/input/?i=" + urllib.quote(self.query.resolve(context))
+            return "/input/?i=" + six.moves.urllib.parse.quote(self.query.resolve(context))
 
 @register.tag(name='make_query_link')
 def do_make_query(parser, token):
@@ -47,12 +49,12 @@ def __init__(self, query):
             self.query = template.Variable(query)
 
     def render(self, context):
-        if isinstance(self.query, unicode) or isinstance(self.query, str):
+        if isinstance(self.query, six.text_type) or isinstance(self.query, str):
             q = self.query[1:-1]
         else:
             q = self.query.resolve(context)
 
-        link = '<a href="/input/?i={0}">{1}</a>'.format(urllib.quote(q), q)
+        link = '<a href="/input/?i={0}">{1}</a>'.format(six.moves.urllib.parse.quote(q), q)
         return link
 
 @register.tag(name='make_example')
@@ -83,5 +85,5 @@ def render(self, context):
             buf.append('<span>{}</span>'.format(title))
 
         buf.append('<a href="/input/?i={0}">{1}</a>'.format(
-            urllib.quote(example), example))
+            six.moves.urllib.parse.quote(example), example))
         return ' '.join(buf)