diff options
| -rw-r--r-- | Doc/api/concrete.tex | 11 | ||||
| -rw-r--r-- | Doc/lib/libcmath.tex | 9 | ||||
| -rwxr-xr-x | Lib/test/test_cmath.py | 246 | ||||
| -rw-r--r-- | Misc/NEWS | 5 | ||||
| -rw-r--r-- | Objects/complexobject.c | 49 |
5 files changed, 264 insertions, 56 deletions
diff --git a/Doc/api/concrete.tex b/Doc/api/concrete.tex index e2d3e52..3b2945e 100644 --- a/Doc/api/concrete.tex +++ b/Doc/api/concrete.tex @@ -443,7 +443,9 @@ booleans. The following macros are available, however. \begin{cfuncdesc}{double}{PyFloat_AsDouble}{PyObject *pyfloat} Return a C \ctype{double} representation of the contents of - \var{pyfloat}. + \var{pyfloat}. If \var{pyfloat} is not a Python floating point + object but has a \method{__float__} method, this method will first + be called to convert \var{pyfloat} into a float. \end{cfuncdesc} \begin{cfuncdesc}{double}{PyFloat_AS_DOUBLE}{PyObject *pyfloat} @@ -558,8 +560,11 @@ typedef struct { \end{cfuncdesc} \begin{cfuncdesc}{Py_complex}{PyComplex_AsCComplex}{PyObject *op} - Return the \ctype{Py_complex} value of the complex number - \var{op}. + Return the \ctype{Py_complex} value of the complex number \var{op}. + \versionchanged[If \var{op} is not a Python complex number object + but has a \method{__complex__} method, this method + will first be called to convert \var{op} to a Python + complex number object]{2.6} \end{cfuncdesc} diff --git a/Doc/lib/libcmath.tex b/Doc/lib/libcmath.tex index 54e0cdb..f8aa45b 100644 --- a/Doc/lib/libcmath.tex +++ b/Doc/lib/libcmath.tex @@ -5,7 +5,14 @@ \modulesynopsis{Mathematical functions for complex numbers.} This module is always available. It provides access to mathematical -functions for complex numbers. The functions are: +functions for complex numbers. The functions in this module accept +integers, floating-point numbers or complex numbers as arguments. +They will also accept any Python object that has either a +\method{__complex__} or a \method{__float__} method: these methods are +used to convert the object to a complex or floating-point number, respectively, and +the function is then applied to the result of the conversion. + +The functions are: \begin{funcdesc}{acos}{x} Return the arc cosine of \var{x}. diff --git a/Lib/test/test_cmath.py b/Lib/test/test_cmath.py index 6e39292..7198dae 100755 --- a/Lib/test/test_cmath.py +++ b/Lib/test/test_cmath.py @@ -1,52 +1,196 @@ -#! /usr/bin/env python -""" Simple test script for cmathmodule.c - Roger E. Masse -""" +from test.test_support import run_unittest +import unittest import cmath, math -from test.test_support import verbose, verify, TestFailed - -verify(abs(cmath.log(10) - math.log(10)) < 1e-9) -verify(abs(cmath.log(10,2) - math.log(10,2)) < 1e-9) -try: - cmath.log('a') -except TypeError: - pass -else: - raise TestFailed - -try: - cmath.log(10, 'a') -except TypeError: - pass -else: - raise TestFailed - - -testdict = {'acos' : 1.0, - 'acosh' : 1.0, - 'asin' : 1.0, - 'asinh' : 1.0, - 'atan' : 0.2, - 'atanh' : 0.2, - 'cos' : 1.0, - 'cosh' : 1.0, - 'exp' : 1.0, - 'log' : 1.0, - 'log10' : 1.0, - 'sin' : 1.0, - 'sinh' : 1.0, - 'sqrt' : 1.0, - 'tan' : 1.0, - 'tanh' : 1.0} - -for func in testdict.keys(): - f = getattr(cmath, func) - r = f(testdict[func]) - if verbose: - print 'Calling %s(%f) = %f' % (func, testdict[func], abs(r)) - -p = cmath.pi -e = cmath.e -if verbose: - print 'PI = ', abs(p) - print 'E = ', abs(e) + +class CMathTests(unittest.TestCase): + # list of all functions in cmath + test_functions = [getattr(cmath, fname) for fname in [ + 'acos', 'acosh', 'asin', 'asinh', 'atan', 'atanh', + 'cos', 'cosh', 'exp', 'log', 'log10', 'sin', 'sinh', + 'sqrt', 'tan', 'tanh']] + # test first and second arguments independently for 2-argument log + test_functions.append(lambda x : cmath.log(x, 1729. + 0j)) + test_functions.append(lambda x : cmath.log(14.-27j, x)) + + def cAssertAlmostEqual(self, a, b, rel_eps = 1e-10, abs_eps = 1e-100): + """Check that two complex numbers are almost equal.""" + # the two complex numbers are considered almost equal if + # either the relative error is <= rel_eps or the absolute error + # is tiny, <= abs_eps. + if a == b == 0: + return + absolute_error = abs(a-b) + relative_error = absolute_error/max(abs(a), abs(b)) + if relative_error > rel_eps and absolute_error > abs_eps: + self.fail("%s and %s are not almost equal" % (a, b)) + + def test_constants(self): + e_expected = 2.71828182845904523536 + pi_expected = 3.14159265358979323846 + self.assertAlmostEqual(cmath.pi, pi_expected, 9, + "cmath.pi is %s; should be %s" % (cmath.pi, pi_expected)) + self.assertAlmostEqual(cmath.e, e_expected, 9, + "cmath.e is %s; should be %s" % (cmath.e, e_expected)) + + def test_user_object(self): + # Test automatic calling of __complex__ and __float__ by cmath + # functions + + # some random values to use as test values; we avoid values + # for which any of the functions in cmath is undefined + # (i.e. 0., 1., -1., 1j, -1j) or would cause overflow + cx_arg = 4.419414439 + 1.497100113j + flt_arg = -6.131677725 + + # a variety of non-complex numbers, used to check that + # non-complex return values from __complex__ give an error + non_complexes = ["not complex", 1, 5L, 2., None, + object(), NotImplemented] + + # Now we introduce a variety of classes whose instances might + # end up being passed to the cmath functions + + # usual case: new-style class implementing __complex__ + class MyComplex(object): + def __init__(self, value): + self.value = value + def __complex__(self): + return self.value + + # old-style class implementing __complex__ + class MyComplexOS: + def __init__(self, value): + self.value = value + def __complex__(self): + return self.value + + # classes for which __complex__ raises an exception + class SomeException(Exception): + pass + class MyComplexException(object): + def __complex__(self): + raise SomeException + class MyComplexExceptionOS: + def __complex__(self): + raise SomeException + + # some classes not providing __float__ or __complex__ + class NeitherComplexNorFloat(object): + pass + class NeitherComplexNorFloatOS: + pass + class MyInt(object): + def __int__(self): return 2 + def __long__(self): return 2L + def __index__(self): return 2 + class MyIntOS: + def __int__(self): return 2 + def __long__(self): return 2L + def __index__(self): return 2 + + # other possible combinations of __float__ and __complex__ + # that should work + class FloatAndComplex(object): + def __float__(self): + return flt_arg + def __complex__(self): + return cx_arg + class FloatAndComplexOS: + def __float__(self): + return flt_arg + def __complex__(self): + return cx_arg + class JustFloat(object): + def __float__(self): + return flt_arg + class JustFloatOS: + def __float__(self): + return flt_arg + + for f in self.test_functions: + # usual usage + self.cAssertAlmostEqual(f(MyComplex(cx_arg)), f(cx_arg)) + self.cAssertAlmostEqual(f(MyComplexOS(cx_arg)), f(cx_arg)) + # other combinations of __float__ and __complex__ + self.cAssertAlmostEqual(f(FloatAndComplex()), f(cx_arg)) + self.cAssertAlmostEqual(f(FloatAndComplexOS()), f(cx_arg)) + self.cAssertAlmostEqual(f(JustFloat()), f(flt_arg)) + self.cAssertAlmostEqual(f(JustFloatOS()), f(flt_arg)) + # TypeError should be raised for classes not providing + # either __complex__ or __float__, even if they provide + # __int__, __long__ or __index__. An old-style class + # currently raises AttributeError instead of a TypeError; + # this could be considered a bug. + self.assertRaises(TypeError, f, NeitherComplexNorFloat()) + self.assertRaises(TypeError, f, MyInt()) + self.assertRaises(Exception, f, NeitherComplexNorFloatOS()) + self.assertRaises(Exception, f, MyIntOS()) + # non-complex return value from __complex__ -> TypeError + for bad_complex in non_complexes: + self.assertRaises(TypeError, f, MyComplex(bad_complex)) + self.assertRaises(TypeError, f, MyComplexOS(bad_complex)) + # exceptions in __complex__ should be propagated correctly + self.assertRaises(SomeException, f, MyComplexException()) + self.assertRaises(SomeException, f, MyComplexExceptionOS()) + + def test_input_type(self): + # ints and longs should be acceptable inputs to all cmath + # functions, by virtue of providing a __float__ method + for f in self.test_functions: + for arg in [2, 2L, 2.]: + self.cAssertAlmostEqual(f(arg), f(arg.__float__())) + + # but strings should give a TypeError + for f in self.test_functions: + for arg in ["a", "long_string", "0", "1j", ""]: + self.assertRaises(TypeError, f, arg) + + def test_cmath_matches_math(self): + # check that corresponding cmath and math functions are equal + # for floats in the appropriate range + + # test_values in (0, 1) + test_values = [0.01, 0.1, 0.2, 0.5, 0.9, 0.99] + + # test_values for functions defined on [-1., 1.] + unit_interval = test_values + [-x for x in test_values] + \ + [0., 1., -1.] + + # test_values for log, log10, sqrt + positive = test_values + [1.] + [1./x for x in test_values] + nonnegative = [0.] + positive + + # test_values for functions defined on the whole real line + real_line = [0.] + positive + [-x for x in positive] + + test_functions = { + 'acos' : unit_interval, + 'asin' : unit_interval, + 'atan' : real_line, + 'cos' : real_line, + 'cosh' : real_line, + 'exp' : real_line, + 'log' : positive, + 'log10' : positive, + 'sin' : real_line, + 'sinh' : real_line, + 'sqrt' : nonnegative, + 'tan' : real_line, + 'tanh' : real_line} + + for fn, values in test_functions.items(): + float_fn = getattr(math, fn) + complex_fn = getattr(cmath, fn) + for v in values: + self.cAssertAlmostEqual(float_fn(v), complex_fn(v)) + + # test two-argument version of log with various bases + for base in [0.5, 2., 10.]: + for v in positive: + self.cAssertAlmostEqual(cmath.log(v, base), math.log(v, base)) + +def test_main(): + run_unittest(CMathTests) + +if __name__ == "__main__": + test_main() @@ -12,6 +12,11 @@ What's New in Python 2.6 alpha 1? Core and builtins ----------------- +- Patch #1675423: PyComplex_AsCComplex() now tries to convert an object + to complex using its __complex__() method before falling back to the + __float__() method. Therefore, the functions in the cmath module now + can operate on objects that define a __complex__() method. + - Patch #1623563: allow __class__ assignment for classes with __slots__. The old and the new class are still required to have the same slot names. diff --git a/Objects/complexobject.c b/Objects/complexobject.c index 54ad075..a8a2188 100644 --- a/Objects/complexobject.c +++ b/Objects/complexobject.c @@ -252,12 +252,59 @@ Py_complex PyComplex_AsCComplex(PyObject *op) { Py_complex cv; + PyObject *newop = NULL; + static PyObject *complex_str = NULL; + + assert(op); + /* If op is already of type PyComplex_Type, return its value */ if (PyComplex_Check(op)) { return ((PyComplexObject *)op)->cval; } + /* If not, use op's __complex__ method, if it exists */ + + /* return -1 on failure */ + cv.real = -1.; + cv.imag = 0.; + + if (PyInstance_Check(op)) { + /* this can go away in python 3000 */ + if (PyObject_HasAttrString(op, "__complex__")) { + newop = PyObject_CallMethod(op, "__complex__", NULL); + if (!newop) + return cv; + } + /* else try __float__ */ + } else { + PyObject *complexfunc; + if (!complex_str) { + if (!(complex_str = PyString_FromString("__complex__"))) + return cv; + } + complexfunc = _PyType_Lookup(op->ob_type, complex_str); + /* complexfunc is a borrowed reference */ + if (complexfunc) { + newop = PyObject_CallFunctionObjArgs(complexfunc, op, NULL); + if (!newop) + return cv; + } + } + + if (newop) { + if (!PyComplex_Check(newop)) { + PyErr_SetString(PyExc_TypeError, + "__complex__ should return a complex object"); + Py_DECREF(newop); + return cv; + } + cv = ((PyComplexObject *)newop)->cval; + Py_DECREF(newop); + return cv; + } + /* If neither of the above works, interpret op as a float giving the + real part of the result, and fill in the imaginary part as 0. */ else { + /* PyFloat_AsDouble will return -1 on failure */ cv.real = PyFloat_AsDouble(op); - cv.imag = 0.; return cv; } } |