- add scipycompat for compatibility with non-scipy

- support Python 2.5 - add tox.ini for testing with Tox
sublee · Nov 13, 2012 · 80f8875 · 80f8875
1 parent 4a7d0f8
commit 80f8875
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diff --git a/tox.ini b/tox.ini
@@ -0,0 +1,6 @@
+[tox]
+envlist = py25, py26, py27, pypy
+
+[testenv]
+deps = Attest
+commands = python -m attest.run trueskilltests.suite
diff --git a/trueskill/__init__.py b/trueskill/__init__.py
@@ -13,8 +13,8 @@
 import math
 
 from .mathematics import cdf, pdf, ppf, Gaussian, Matrix
-from .factorgraph import (
-    Variable, PriorFactor, LikelihoodFactor, SumFactor, TruncateFactor)
+from .factorgraph import (Variable, PriorFactor, LikelihoodFactor, SumFactor,
+                          TruncateFactor)
 
 
 __copyright__ = 'Copyright 2012 by Heungsub Lee'
@@ -241,10 +241,10 @@ def build_factor_graph(self, rating_groups, ranks):
         team_sizes = _team_sizes(rating_groups)
         # layer builders
         def build_rating_layer():
-            for rating_var, rating in zip(rating_vars, ratings):
+            for rating_var, rating in itertools.izip(rating_vars, ratings):
                 yield PriorFactor(rating_var, rating, self.tau)
         def build_perf_layer():
-            for rating_var, perf_var in zip(rating_vars, perf_vars):
+            for rating_var, perf_var in itertools.izip(rating_vars, perf_vars):
                 yield LikelihoodFactor(rating_var, perf_var, self.beta ** 2)
         def build_teamperf_layer():
             for team, teamperf_var in enumerate(teamperf_vars):
@@ -271,11 +271,9 @@ def build_trunc_layer():
                     v_func, w_func = v_win, w_win
                 yield TruncateFactor(teamdiff_var, v_func, w_func, draw_margin)
         # build layers
-        return (
-            list(build_rating_layer()), list(build_perf_layer()),
-            list(build_teamperf_layer()), list(build_teamdiff_layer()),
-            list(build_trunc_layer())
-        )
+        return (list(build_rating_layer()), list(build_perf_layer()),
+                list(build_teamperf_layer()), list(build_teamdiff_layer()),
+                list(build_trunc_layer()))
 
     def run_schedule(self, rating_layer, perf_layer, teamperf_layer,
                      teamdiff_layer, trunc_layer, min_delta=DELTA):
@@ -364,7 +362,8 @@ def compare(x, y):
         unsorting_hint = [x for x, (r, g) in sorting]
         # build factor graph
         layers = self.build_factor_graph(sorted_groups, sorted_ranks)
-        self.run_schedule(*layers, min_delta=min_delta)
+        args = layers + (min_delta,)
+        self.run_schedule(*args)
         # make result
         rating_layer, team_sizes = layers[0], _team_sizes(sorted_groups)
         transformed_groups = []

diff --git a/trueskill/mathematics.py b/trueskill/mathematics.py
@@ -9,59 +9,23 @@
     :copyright: (c) 2012 by Heungsub Lee.
     :license: BSD, see LICENSE for more details.
 """
+from __future__ import absolute_import
 import copy
 import math
-from numbers import Number
-
-
-__all__ = 'cdf', 'pdf', 'ppf', 'Gaussian', 'Matrix'
-
+try:
+    from numbers import Number
+except ImportError:
+    Number = (int, long, float, complex)
 
 try:
     from scipy.stats import norm
-    cdf, pdf, ppf = norm.cdf, norm.pdf, norm.ppf
 except ImportError:
+    from .scipycompat import cdf, pdf, ppf
+else:
+    cdf, pdf, ppf = norm.cdf, norm.pdf, norm.ppf
+
 
-    def erfcc(x):
-        """Complementary error function (via http://bit.ly/zOLqbc)"""
-        z = abs(x)
-        t = 1. / (1. + z / 2.)
-        r = t * math.exp(-z * z - 1.26551223 + t * (1.00002368 + t * (
-                         0.37409196 + t * (0.09678418 + t * (
-                         -0.18628806 + t * (0.27886807 + t * (
-                         -1.13520398 + t * (1.48851587 + t * (
-                         -0.82215223 + t * 0.17087277)))))))))
-        return 2. - r if x < 0 else r
-
-    def ierfcc(y):
-        """The inverse function of erfcc"""
-        if y >= 2:
-            return -100
-        elif y <= 0:
-            return 100
-        zero_point = y < 1
-        if not zero_point:
-            y = 2 - y
-        t = math.sqrt(-2 * math.log(y / 2.))
-        x = -0.70711 * \
-            ((2.30753 + t * 0.27061) / (1. + t * (0.99229 + t * 0.04481)) - t)
-        for i in xrange(2):
-            err = erfcc(x) - y
-            x += err / (1.12837916709551257 * math.exp(-(x ** 2)) - x * err)
-        return x if zero_point else -x
-
-    def cdf(x, mu=0, sigma=1):
-        """Cumulative distribution function"""
-        return 0.5 * erfcc(-(x - mu) / (sigma * math.sqrt(2)))
-
-    def pdf(x, mu=0, sigma=1):
-        """Probability density function"""
-        return (1 / math.sqrt(2 * math.pi) * abs(sigma)) * \
-            math.exp(-(((x - mu) / abs(sigma)) ** 2 / 2))
-
-    def ppf(x, mu=0, sigma=1):
-        """The inverse function of CDF"""
-        return mu - sigma * math.sqrt(2) * ierfcc(2 * x)
+__all__ = ['cdf', 'pdf', 'ppf', 'Gaussian', 'Matrix']
 
 
 class Gaussian(object):

diff --git a/trueskill/scipycompat.py b/trueskill/scipycompat.py
@@ -0,0 +1,62 @@
+# -*- coding: utf-8 -*-
+"""
+    trueskill.scipycompat
+    ~~~~~~~~~~~~~~~~~~~~~
+
+    A fallback of `scipy`_.
+
+    .. _scipy:: http://www.scipy.org/
+
+    :copyright: (c) 2012 by Heungsub Lee.
+    :license: BSD, see LICENSE for more details.
+"""
+import math
+
+
+__all__ = ['cdf', 'pdf', 'ppf']
+
+
+def erfcc(x):
+    """Complementary error function (via http://bit.ly/zOLqbc)"""
+    z = abs(x)
+    t = 1. / (1. + z / 2.)
+    r = t * math.exp(-z * z - 1.26551223 + t * (1.00002368 + t * (
+                     0.37409196 + t * (0.09678418 + t * (
+                     -0.18628806 + t * (0.27886807 + t * (
+                     -1.13520398 + t * (1.48851587 + t * (
+                     -0.82215223 + t * 0.17087277)))))))))
+    return 2. - r if x < 0 else r
+
+
+def ierfcc(y):
+    """The inverse function of erfcc"""
+    if y >= 2:
+        return -100
+    elif y <= 0:
+        return 100
+    zero_point = y < 1
+    if not zero_point:
+        y = 2 - y
+    t = math.sqrt(-2 * math.log(y / 2.))
+    x = -0.70711 * \
+        ((2.30753 + t * 0.27061) / (1. + t * (0.99229 + t * 0.04481)) - t)
+    for i in xrange(2):
+        err = erfcc(x) - y
+        x += err / (1.12837916709551257 * math.exp(-(x ** 2)) - x * err)
+    return x if zero_point else -x
+
+
+def cdf(x, mu=0, sigma=1):
+    """Cumulative distribution function"""
+    return 0.5 * erfcc(-(x - mu) / (sigma * math.sqrt(2)))
+
+
+def pdf(x, mu=0, sigma=1):
+    """Probability density function"""
+    return (1 / math.sqrt(2 * math.pi) * abs(sigma)) * \
+        math.exp(-(((x - mu) / abs(sigma)) ** 2 / 2))
+
+
+def ppf(x, mu=0, sigma=1):
+    """The inverse function of CDF"""
+    return mu - sigma * math.sqrt(2) * ierfcc(2 * x)
diff --git a/trueskilltests.py b/trueskilltests.py
@@ -1,4 +1,6 @@
 # -*- coding: utf-8 -*-
+from __future__ import with_statement
+import sys
 import warnings
 
 from attest import Tests, assert_hook, raises
@@ -91,7 +93,8 @@ def invalid_rating_groups():
         env.validate_rating_groups([(Rating(),), {0: Rating()}])
 
 
-@suite.test
+# there's no warnings.catch_warnings under Python 2.6
+@suite.test_if(sys.version_info >= (2, 6))
 def deprecated_methods():
     env = TrueSkill()
     r1, r2, r3 = Rating(), Rating(), Rating()
@@ -122,6 +125,9 @@ def deprecated_individual_rating_groups():
         rate([r1, r2, r3])
     with raises(TypeError):
         quality([r1, r2, r3])
+    if sys.version_info < (2, 6):
+        # there's no warnings.catch_warnings under Python 2.6
+        return
     # deprecated methods accept individual rating groups
     with warnings.catch_warnings():
         warnings.simplefilter('ignore')
@@ -214,7 +220,10 @@ def almost_equals(self, val1, val2):
         else:
             if round(val1, self.precision) == round(val2, self.precision):
                 return True
-            fmt = '%.{0}f'.format(self.precision)
+            try:
+                fmt = '%.{0}f'.format(self.precision)
+            except AttributeError:
+                fmt = '%%.%df' % self.precision
             mantissa = lambda f: int((fmt % f).replace('.', ''))
             return abs(mantissa(val1) - mantissa(val2)) <= 1