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1from test.support import requires_IEEE_754, cpython_only, import_helper
2from test.support.testcase import ComplexesAreIdenticalMixin
3from test.test_math import parse_testfile, test_file
4import test.test_math as test_math
5import unittest
6import cmath, math
7from cmath import phase, polar, rect, pi
8import platform
9import sys
10
11
12INF = float('inf')
13NAN = float('nan')
14
15complex_zeros = [complex(x, y) for x in [0.0, -0.0] for y in [0.0, -0.0]]
16complex_infinities = [complex(x, y) for x, y in [
17        (INF, 0.0),  # 1st quadrant
18        (INF, 2.3),
19        (INF, INF),
20        (2.3, INF),
21        (0.0, INF),
22        (-0.0, INF), # 2nd quadrant
23        (-2.3, INF),
24        (-INF, INF),
25        (-INF, 2.3),
26        (-INF, 0.0),
27        (-INF, -0.0), # 3rd quadrant
28        (-INF, -2.3),
29        (-INF, -INF),
30        (-2.3, -INF),
31        (-0.0, -INF),
32        (0.0, -INF), # 4th quadrant
33        (2.3, -INF),
34        (INF, -INF),
35        (INF, -2.3),
36        (INF, -0.0)
37        ]]
38complex_nans = [complex(x, y) for x, y in [
39        (NAN, -INF),
40        (NAN, -2.3),
41        (NAN, -0.0),
42        (NAN, 0.0),
43        (NAN, 2.3),
44        (NAN, INF),
45        (-INF, NAN),
46        (-2.3, NAN),
47        (-0.0, NAN),
48        (0.0, NAN),
49        (2.3, NAN),
50        (INF, NAN)
51        ]]
52
53class CMathTests(ComplexesAreIdenticalMixin, unittest.TestCase):
54    # list of all functions in cmath
55    test_functions = [getattr(cmath, fname) for fname in [
56            'acos', 'acosh', 'asin', 'asinh', 'atan', 'atanh',
57            'cos', 'cosh', 'exp', 'log', 'log10', 'sin', 'sinh',
58            'sqrt', 'tan', 'tanh']]
59    # test first and second arguments independently for 2-argument log
60    test_functions.append(lambda x : cmath.log(x, 1729. + 0j))
61    test_functions.append(lambda x : cmath.log(14.-27j, x))
62
63    def setUp(self):
64        self.test_values = open(test_file, encoding="utf-8")
65
66    def tearDown(self):
67        self.test_values.close()
68
69    def rAssertAlmostEqual(self, a, b, rel_err = 2e-15, abs_err = 5e-323,
70                           msg=None):
71        """Fail if the two floating-point numbers are not almost equal.
72
73        Determine whether floating-point values a and b are equal to within
74        a (small) rounding error.  The default values for rel_err and
75        abs_err are chosen to be suitable for platforms where a float is
76        represented by an IEEE 754 double.  They allow an error of between
77        9 and 19 ulps.
78        """
79
80        # special values testing
81        if math.isnan(a):
82            if math.isnan(b):
83                return
84            self.fail(msg or '{!r} should be nan'.format(b))
85
86        if math.isinf(a):
87            if a == b:
88                return
89            self.fail(msg or 'finite result where infinity expected: '
90                      'expected {!r}, got {!r}'.format(a, b))
91
92        # if both a and b are zero, check whether they have the same sign
93        # (in theory there are examples where it would be legitimate for a
94        # and b to have opposite signs; in practice these hardly ever
95        # occur).
96        if not a and not b:
97            if math.copysign(1., a) != math.copysign(1., b):
98                self.fail(msg or 'zero has wrong sign: expected {!r}, '
99                          'got {!r}'.format(a, b))
100
101        # if a-b overflows, or b is infinite, return False.  Again, in
102        # theory there are examples where a is within a few ulps of the
103        # max representable float, and then b could legitimately be
104        # infinite.  In practice these examples are rare.
105        try:
106            absolute_error = abs(b-a)
107        except OverflowError:
108            pass
109        else:
110            # test passes if either the absolute error or the relative
111            # error is sufficiently small.  The defaults amount to an
112            # error of between 9 ulps and 19 ulps on an IEEE-754 compliant
113            # machine.
114            if absolute_error <= max(abs_err, rel_err * abs(a)):
115                return
116        self.fail(msg or
117                  '{!r} and {!r} are not sufficiently close'.format(a, b))
118
119    def test_constants(self):
120        e_expected = 2.71828182845904523536
121        pi_expected = 3.14159265358979323846
122        self.assertAlmostEqual(cmath.pi, pi_expected, places=9,
123            msg="cmath.pi is {}; should be {}".format(cmath.pi, pi_expected))
124        self.assertAlmostEqual(cmath.e, e_expected, places=9,
125            msg="cmath.e is {}; should be {}".format(cmath.e, e_expected))
126
127    def test_infinity_and_nan_constants(self):
128        self.assertEqual(cmath.inf.real, math.inf)
129        self.assertEqual(cmath.inf.imag, 0.0)
130        self.assertEqual(cmath.infj.real, 0.0)
131        self.assertEqual(cmath.infj.imag, math.inf)
132
133        self.assertTrue(math.isnan(cmath.nan.real))
134        self.assertEqual(cmath.nan.imag, 0.0)
135        self.assertEqual(cmath.nanj.real, 0.0)
136        self.assertTrue(math.isnan(cmath.nanj.imag))
137        # Also check that the sign of all of these is positive:
138        self.assertEqual(math.copysign(1., cmath.nan.real), 1.)
139        self.assertEqual(math.copysign(1., cmath.nan.imag), 1.)
140        self.assertEqual(math.copysign(1., cmath.nanj.real), 1.)
141        self.assertEqual(math.copysign(1., cmath.nanj.imag), 1.)
142
143        # Check consistency with reprs.
144        self.assertEqual(repr(cmath.inf), "inf")
145        self.assertEqual(repr(cmath.infj), "infj")
146        self.assertEqual(repr(cmath.nan), "nan")
147        self.assertEqual(repr(cmath.nanj), "nanj")
148
149    def test_user_object(self):
150        # Test automatic calling of __complex__ and __float__ by cmath
151        # functions
152
153        # some random values to use as test values; we avoid values
154        # for which any of the functions in cmath is undefined
155        # (i.e. 0., 1., -1., 1j, -1j) or would cause overflow
156        cx_arg = 4.419414439 + 1.497100113j
157        flt_arg = -6.131677725
158
159        # a variety of non-complex numbers, used to check that
160        # non-complex return values from __complex__ give an error
161        non_complexes = ["not complex", 1, 5, 2., None,
162                         object(), NotImplemented]
163
164        # Now we introduce a variety of classes whose instances might
165        # end up being passed to the cmath functions
166
167        # usual case: new-style class implementing __complex__
168        class MyComplex:
169            def __init__(self, value):
170                self.value = value
171            def __complex__(self):
172                return self.value
173
174        # classes for which __complex__ raises an exception
175        class SomeException(Exception):
176            pass
177        class MyComplexException:
178            def __complex__(self):
179                raise SomeException
180
181        # some classes not providing __float__ or __complex__
182        class NeitherComplexNorFloat(object):
183            pass
184        class Index:
185            def __int__(self): return 2
186            def __index__(self): return 2
187        class MyInt:
188            def __int__(self): return 2
189
190        # other possible combinations of __float__ and __complex__
191        # that should work
192        class FloatAndComplex:
193            def __float__(self):
194                return flt_arg
195            def __complex__(self):
196                return cx_arg
197        class JustFloat:
198            def __float__(self):
199                return flt_arg
200
201        for f in self.test_functions:
202            # usual usage
203            self.assertEqual(f(MyComplex(cx_arg)), f(cx_arg))
204            # other combinations of __float__ and __complex__
205            self.assertEqual(f(FloatAndComplex()), f(cx_arg))
206            self.assertEqual(f(JustFloat()), f(flt_arg))
207            self.assertEqual(f(Index()), f(int(Index())))
208            # TypeError should be raised for classes not providing
209            # either __complex__ or __float__, even if they provide
210            # __int__ or __index__:
211            self.assertRaises(TypeError, f, NeitherComplexNorFloat())
212            self.assertRaises(TypeError, f, MyInt())
213            # non-complex return value from __complex__ -> TypeError
214            for bad_complex in non_complexes:
215                self.assertRaises(TypeError, f, MyComplex(bad_complex))
216            # exceptions in __complex__ should be propagated correctly
217            self.assertRaises(SomeException, f, MyComplexException())
218
219    def test_input_type(self):
220        # ints should be acceptable inputs to all cmath
221        # functions, by virtue of providing a __float__ method
222        for f in self.test_functions:
223            for arg in [2, 2.]:
224                self.assertEqual(f(arg), f(arg.__float__()))
225
226        # but strings should give a TypeError
227        for f in self.test_functions:
228            for arg in ["a", "long_string", "0", "1j", ""]:
229                self.assertRaises(TypeError, f, arg)
230
231    def test_cmath_matches_math(self):
232        # check that corresponding cmath and math functions are equal
233        # for floats in the appropriate range
234
235        # test_values in (0, 1)
236        test_values = [0.01, 0.1, 0.2, 0.5, 0.9, 0.99]
237
238        # test_values for functions defined on [-1., 1.]
239        unit_interval = test_values + [-x for x in test_values] + \
240            [0., 1., -1.]
241
242        # test_values for log, log10, sqrt
243        positive = test_values + [1.] + [1./x for x in test_values]
244        nonnegative = [0.] + positive
245
246        # test_values for functions defined on the whole real line
247        real_line = [0.] + positive + [-x for x in positive]
248
249        test_functions = {
250            'acos' : unit_interval,
251            'asin' : unit_interval,
252            'atan' : real_line,
253            'cos' : real_line,
254            'cosh' : real_line,
255            'exp' : real_line,
256            'log' : positive,
257            'log10' : positive,
258            'sin' : real_line,
259            'sinh' : real_line,
260            'sqrt' : nonnegative,
261            'tan' : real_line,
262            'tanh' : real_line}
263
264        for fn, values in test_functions.items():
265            float_fn = getattr(math, fn)
266            complex_fn = getattr(cmath, fn)
267            for v in values:
268                z = complex_fn(v)
269                self.rAssertAlmostEqual(float_fn(v), z.real)
270                self.assertEqual(0., z.imag)
271
272        # test two-argument version of log with various bases
273        for base in [0.5, 2., 10.]:
274            for v in positive:
275                z = cmath.log(v, base)
276                self.rAssertAlmostEqual(math.log(v, base), z.real)
277                self.assertEqual(0., z.imag)
278
279    @requires_IEEE_754
280    def test_specific_values(self):
281        # Some tests need to be skipped on ancient OS X versions.
282        # See issue #27953.
283        SKIP_ON_TIGER = {'tan0064'}
284
285        osx_version = None
286        if sys.platform == 'darwin':
287            version_txt = platform.mac_ver()[0]
288            try:
289                osx_version = tuple(map(int, version_txt.split('.')))
290            except ValueError:
291                pass
292
293        def rect_complex(z):
294            """Wrapped version of rect that accepts a complex number instead of
295            two float arguments."""
296            return cmath.rect(z.real, z.imag)
297
298        def polar_complex(z):
299            """Wrapped version of polar that returns a complex number instead of
300            two floats."""
301            return complex(*polar(z))
302
303        for id, fn, ar, ai, er, ei, flags in parse_testfile(test_file):
304            arg = complex(ar, ai)
305            expected = complex(er, ei)
306
307            # Skip certain tests on OS X 10.4.
308            if osx_version is not None and osx_version < (10, 5):
309                if id in SKIP_ON_TIGER:
310                    continue
311
312            if fn == 'rect':
313                function = rect_complex
314            elif fn == 'polar':
315                function = polar_complex
316            else:
317                function = getattr(cmath, fn)
318            if 'divide-by-zero' in flags or 'invalid' in flags:
319                try:
320                    actual = function(arg)
321                except ValueError:
322                    continue
323                else:
324                    self.fail('ValueError not raised in test '
325                          '{}: {}(complex({!r}, {!r}))'.format(id, fn, ar, ai))
326
327            if 'overflow' in flags:
328                try:
329                    actual = function(arg)
330                except OverflowError:
331                    continue
332                else:
333                    self.fail('OverflowError not raised in test '
334                          '{}: {}(complex({!r}, {!r}))'.format(id, fn, ar, ai))
335
336            actual = function(arg)
337
338            if 'ignore-real-sign' in flags:
339                actual = complex(abs(actual.real), actual.imag)
340                expected = complex(abs(expected.real), expected.imag)
341            if 'ignore-imag-sign' in flags:
342                actual = complex(actual.real, abs(actual.imag))
343                expected = complex(expected.real, abs(expected.imag))
344
345            # for the real part of the log function, we allow an
346            # absolute error of up to 2e-15.
347            if fn in ('log', 'log10'):
348                real_abs_err = 2e-15
349            else:
350                real_abs_err = 5e-323
351
352            error_message = (
353                '{}: {}(complex({!r}, {!r}))\n'
354                'Expected: complex({!r}, {!r})\n'
355                'Received: complex({!r}, {!r})\n'
356                'Received value insufficiently close to expected value.'
357                ).format(id, fn, ar, ai,
358                     expected.real, expected.imag,
359                     actual.real, actual.imag)
360            self.rAssertAlmostEqual(expected.real, actual.real,
361                                        abs_err=real_abs_err,
362                                        msg=error_message)
363            self.rAssertAlmostEqual(expected.imag, actual.imag,
364                                        msg=error_message)
365
366    def check_polar(self, func):
367        def check(arg, expected):
368            got = func(arg)
369            for e, g in zip(expected, got):
370                self.rAssertAlmostEqual(e, g)
371        check(0, (0., 0.))
372        check(1, (1., 0.))
373        check(-1, (1., pi))
374        check(1j, (1., pi / 2))
375        check(-3j, (3., -pi / 2))
376        inf = float('inf')
377        check(complex(inf, 0), (inf, 0.))
378        check(complex(-inf, 0), (inf, pi))
379        check(complex(3, inf), (inf, pi / 2))
380        check(complex(5, -inf), (inf, -pi / 2))
381        check(complex(inf, inf), (inf, pi / 4))
382        check(complex(inf, -inf), (inf, -pi / 4))
383        check(complex(-inf, inf), (inf, 3 * pi / 4))
384        check(complex(-inf, -inf), (inf, -3 * pi / 4))
385        nan = float('nan')
386        check(complex(nan, 0), (nan, nan))
387        check(complex(0, nan), (nan, nan))
388        check(complex(nan, nan), (nan, nan))
389        check(complex(inf, nan), (inf, nan))
390        check(complex(-inf, nan), (inf, nan))
391        check(complex(nan, inf), (inf, nan))
392        check(complex(nan, -inf), (inf, nan))
393
394    def test_polar(self):
395        self.check_polar(polar)
396
397    @cpython_only
398    def test_polar_errno(self):
399        # Issue #24489: check a previously set C errno doesn't disturb polar()
400        _testcapi = import_helper.import_module('_testcapi')
401        def polar_with_errno_set(z):
402            _testcapi.set_errno(11)
403            try:
404                return polar(z)
405            finally:
406                _testcapi.set_errno(0)
407        self.check_polar(polar_with_errno_set)
408
409    def test_phase(self):
410        self.assertAlmostEqual(phase(0), 0.)
411        self.assertAlmostEqual(phase(1.), 0.)
412        self.assertAlmostEqual(phase(-1.), pi)
413        self.assertAlmostEqual(phase(-1.+1E-300j), pi)
414        self.assertAlmostEqual(phase(-1.-1E-300j), -pi)
415        self.assertAlmostEqual(phase(1j), pi/2)
416        self.assertAlmostEqual(phase(-1j), -pi/2)
417
418        # zeros
419        self.assertEqual(phase(complex(0.0, 0.0)), 0.0)
420        self.assertEqual(phase(complex(0.0, -0.0)), -0.0)
421        self.assertEqual(phase(complex(-0.0, 0.0)), pi)
422        self.assertEqual(phase(complex(-0.0, -0.0)), -pi)
423
424        # infinities
425        self.assertAlmostEqual(phase(complex(-INF, -0.0)), -pi)
426        self.assertAlmostEqual(phase(complex(-INF, -2.3)), -pi)
427        self.assertAlmostEqual(phase(complex(-INF, -INF)), -0.75*pi)
428        self.assertAlmostEqual(phase(complex(-2.3, -INF)), -pi/2)
429        self.assertAlmostEqual(phase(complex(-0.0, -INF)), -pi/2)
430        self.assertAlmostEqual(phase(complex(0.0, -INF)), -pi/2)
431        self.assertAlmostEqual(phase(complex(2.3, -INF)), -pi/2)
432        self.assertAlmostEqual(phase(complex(INF, -INF)), -pi/4)
433        self.assertEqual(phase(complex(INF, -2.3)), -0.0)
434        self.assertEqual(phase(complex(INF, -0.0)), -0.0)
435        self.assertEqual(phase(complex(INF, 0.0)), 0.0)
436        self.assertEqual(phase(complex(INF, 2.3)), 0.0)
437        self.assertAlmostEqual(phase(complex(INF, INF)), pi/4)
438        self.assertAlmostEqual(phase(complex(2.3, INF)), pi/2)
439        self.assertAlmostEqual(phase(complex(0.0, INF)), pi/2)
440        self.assertAlmostEqual(phase(complex(-0.0, INF)), pi/2)
441        self.assertAlmostEqual(phase(complex(-2.3, INF)), pi/2)
442        self.assertAlmostEqual(phase(complex(-INF, INF)), 0.75*pi)
443        self.assertAlmostEqual(phase(complex(-INF, 2.3)), pi)
444        self.assertAlmostEqual(phase(complex(-INF, 0.0)), pi)
445
446        # real or imaginary part NaN
447        for z in complex_nans:
448            self.assertTrue(math.isnan(phase(z)))
449
450    def test_abs(self):
451        # zeros
452        for z in complex_zeros:
453            self.assertEqual(abs(z), 0.0)
454
455        # infinities
456        for z in complex_infinities:
457            self.assertEqual(abs(z), INF)
458
459        # real or imaginary part NaN
460        self.assertEqual(abs(complex(NAN, -INF)), INF)
461        self.assertTrue(math.isnan(abs(complex(NAN, -2.3))))
462        self.assertTrue(math.isnan(abs(complex(NAN, -0.0))))
463        self.assertTrue(math.isnan(abs(complex(NAN, 0.0))))
464        self.assertTrue(math.isnan(abs(complex(NAN, 2.3))))
465        self.assertEqual(abs(complex(NAN, INF)), INF)
466        self.assertEqual(abs(complex(-INF, NAN)), INF)
467        self.assertTrue(math.isnan(abs(complex(-2.3, NAN))))
468        self.assertTrue(math.isnan(abs(complex(-0.0, NAN))))
469        self.assertTrue(math.isnan(abs(complex(0.0, NAN))))
470        self.assertTrue(math.isnan(abs(complex(2.3, NAN))))
471        self.assertEqual(abs(complex(INF, NAN)), INF)
472        self.assertTrue(math.isnan(abs(complex(NAN, NAN))))
473
474
475    @requires_IEEE_754
476    def test_abs_overflows(self):
477        # result overflows
478        self.assertRaises(OverflowError, abs, complex(1.4e308, 1.4e308))
479
480    def assertCEqual(self, a, b):
481        eps = 1E-7
482        if abs(a.real - b[0]) > eps or abs(a.imag - b[1]) > eps:
483            self.fail((a ,b))
484
485    def test_rect(self):
486        self.assertCEqual(rect(0, 0), (0, 0))
487        self.assertCEqual(rect(1, 0), (1., 0))
488        self.assertCEqual(rect(1, -pi), (-1., 0))
489        self.assertCEqual(rect(1, pi/2), (0, 1.))
490        self.assertCEqual(rect(1, -pi/2), (0, -1.))
491
492    def test_isfinite(self):
493        real_vals = [float('-inf'), -2.3, -0.0,
494                     0.0, 2.3, float('inf'), float('nan')]
495        for x in real_vals:
496            for y in real_vals:
497                z = complex(x, y)
498                self.assertEqual(cmath.isfinite(z),
499                                  math.isfinite(x) and math.isfinite(y))
500
501    def test_isnan(self):
502        self.assertFalse(cmath.isnan(1))
503        self.assertFalse(cmath.isnan(1j))
504        self.assertFalse(cmath.isnan(INF))
505        self.assertTrue(cmath.isnan(NAN))
506        self.assertTrue(cmath.isnan(complex(NAN, 0)))
507        self.assertTrue(cmath.isnan(complex(0, NAN)))
508        self.assertTrue(cmath.isnan(complex(NAN, NAN)))
509        self.assertTrue(cmath.isnan(complex(NAN, INF)))
510        self.assertTrue(cmath.isnan(complex(INF, NAN)))
511
512    def test_isinf(self):
513        self.assertFalse(cmath.isinf(1))
514        self.assertFalse(cmath.isinf(1j))
515        self.assertFalse(cmath.isinf(NAN))
516        self.assertTrue(cmath.isinf(INF))
517        self.assertTrue(cmath.isinf(complex(INF, 0)))
518        self.assertTrue(cmath.isinf(complex(0, INF)))
519        self.assertTrue(cmath.isinf(complex(INF, INF)))
520        self.assertTrue(cmath.isinf(complex(NAN, INF)))
521        self.assertTrue(cmath.isinf(complex(INF, NAN)))
522
523    @requires_IEEE_754
524    def testTanhSign(self):
525        for z in complex_zeros:
526            self.assertComplexesAreIdentical(cmath.tanh(z), z)
527
528    # The algorithm used for atan and atanh makes use of the system
529    # log1p function; If that system function doesn't respect the sign
530    # of zero, then atan and atanh will also have difficulties with
531    # the sign of complex zeros.
532    @requires_IEEE_754
533    def testAtanSign(self):
534        for z in complex_zeros:
535            self.assertComplexesAreIdentical(cmath.atan(z), z)
536
537    @requires_IEEE_754
538    def testAtanhSign(self):
539        for z in complex_zeros:
540            self.assertComplexesAreIdentical(cmath.atanh(z), z)
541
542
543class IsCloseTests(test_math.IsCloseTests):
544    isclose = cmath.isclose
545
546    def test_reject_complex_tolerances(self):
547        with self.assertRaises(TypeError):
548            self.isclose(1j, 1j, rel_tol=1j)
549
550        with self.assertRaises(TypeError):
551            self.isclose(1j, 1j, abs_tol=1j)
552
553        with self.assertRaises(TypeError):
554            self.isclose(1j, 1j, rel_tol=1j, abs_tol=1j)
555
556    def test_complex_values(self):
557        # test complex values that are close to within 12 decimal places
558        complex_examples = [(1.0+1.0j, 1.000000000001+1.0j),
559                            (1.0+1.0j, 1.0+1.000000000001j),
560                            (-1.0+1.0j, -1.000000000001+1.0j),
561                            (1.0-1.0j, 1.0-0.999999999999j),
562                            ]
563
564        self.assertAllClose(complex_examples, rel_tol=1e-12)
565        self.assertAllNotClose(complex_examples, rel_tol=1e-13)
566
567    def test_complex_near_zero(self):
568        # test values near zero that are near to within three decimal places
569        near_zero_examples = [(0.001j, 0),
570                              (0.001, 0),
571                              (0.001+0.001j, 0),
572                              (-0.001+0.001j, 0),
573                              (0.001-0.001j, 0),
574                              (-0.001-0.001j, 0),
575                              ]
576
577        self.assertAllClose(near_zero_examples, abs_tol=1.5e-03)
578        self.assertAllNotClose(near_zero_examples, abs_tol=0.5e-03)
579
580        self.assertIsClose(0.001-0.001j, 0.001+0.001j, abs_tol=2e-03)
581        self.assertIsNotClose(0.001-0.001j, 0.001+0.001j, abs_tol=1e-03)
582
583    def test_complex_special(self):
584        self.assertIsNotClose(INF, INF*1j)
585        self.assertIsNotClose(INF*1j, INF)
586        self.assertIsNotClose(INF, -INF)
587        self.assertIsNotClose(-INF, INF)
588        self.assertIsNotClose(0, INF)
589        self.assertIsNotClose(0, INF*1j)
590
591
592if __name__ == "__main__":
593    unittest.main()
594