123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331 |
- """Tests for binary operators on subtypes of built-in types."""
- import unittest
- from test import test_support
- def gcd(a, b):
- """Greatest common divisor using Euclid's algorithm."""
- while a:
- a, b = b%a, a
- return b
- def isint(x):
- """Test whether an object is an instance of int or long."""
- return isinstance(x, int) or isinstance(x, long)
- def isnum(x):
- """Test whether an object is an instance of a built-in numeric type."""
- for T in int, long, float, complex:
- if isinstance(x, T):
- return 1
- return 0
- def isRat(x):
- """Test wheter an object is an instance of the Rat class."""
- return isinstance(x, Rat)
- class Rat(object):
- """Rational number implemented as a normalized pair of longs."""
- __slots__ = ['_Rat__num', '_Rat__den']
- def __init__(self, num=0L, den=1L):
- """Constructor: Rat([num[, den]]).
- The arguments must be ints or longs, and default to (0, 1)."""
- if not isint(num):
- raise TypeError, "Rat numerator must be int or long (%r)" % num
- if not isint(den):
- raise TypeError, "Rat denominator must be int or long (%r)" % den
- # But the zero is always on
- if den == 0:
- raise ZeroDivisionError, "zero denominator"
- g = gcd(den, num)
- self.__num = long(num//g)
- self.__den = long(den//g)
- def _get_num(self):
- """Accessor function for read-only 'num' attribute of Rat."""
- return self.__num
- num = property(_get_num, None)
- def _get_den(self):
- """Accessor function for read-only 'den' attribute of Rat."""
- return self.__den
- den = property(_get_den, None)
- def __repr__(self):
- """Convert a Rat to a string resembling a Rat constructor call."""
- return "Rat(%d, %d)" % (self.__num, self.__den)
- def __str__(self):
- """Convert a Rat to a string resembling a decimal numeric value."""
- return str(float(self))
- def __float__(self):
- """Convert a Rat to a float."""
- return self.__num*1.0/self.__den
- def __int__(self):
- """Convert a Rat to an int; self.den must be 1."""
- if self.__den == 1:
- try:
- return int(self.__num)
- except OverflowError:
- raise OverflowError, ("%s too large to convert to int" %
- repr(self))
- raise ValueError, "can't convert %s to int" % repr(self)
- def __long__(self):
- """Convert a Rat to a long; self.den must be 1."""
- if self.__den == 1:
- return long(self.__num)
- raise ValueError, "can't convert %s to long" % repr(self)
- def __add__(self, other):
- """Add two Rats, or a Rat and a number."""
- if isint(other):
- other = Rat(other)
- if isRat(other):
- return Rat(self.__num*other.__den + other.__num*self.__den,
- self.__den*other.__den)
- if isnum(other):
- return float(self) + other
- return NotImplemented
- __radd__ = __add__
- def __sub__(self, other):
- """Subtract two Rats, or a Rat and a number."""
- if isint(other):
- other = Rat(other)
- if isRat(other):
- return Rat(self.__num*other.__den - other.__num*self.__den,
- self.__den*other.__den)
- if isnum(other):
- return float(self) - other
- return NotImplemented
- def __rsub__(self, other):
- """Subtract two Rats, or a Rat and a number (reversed args)."""
- if isint(other):
- other = Rat(other)
- if isRat(other):
- return Rat(other.__num*self.__den - self.__num*other.__den,
- self.__den*other.__den)
- if isnum(other):
- return other - float(self)
- return NotImplemented
- def __mul__(self, other):
- """Multiply two Rats, or a Rat and a number."""
- if isRat(other):
- return Rat(self.__num*other.__num, self.__den*other.__den)
- if isint(other):
- return Rat(self.__num*other, self.__den)
- if isnum(other):
- return float(self)*other
- return NotImplemented
- __rmul__ = __mul__
- def __truediv__(self, other):
- """Divide two Rats, or a Rat and a number."""
- if isRat(other):
- return Rat(self.__num*other.__den, self.__den*other.__num)
- if isint(other):
- return Rat(self.__num, self.__den*other)
- if isnum(other):
- return float(self) / other
- return NotImplemented
- __div__ = __truediv__
- def __rtruediv__(self, other):
- """Divide two Rats, or a Rat and a number (reversed args)."""
- if isRat(other):
- return Rat(other.__num*self.__den, other.__den*self.__num)
- if isint(other):
- return Rat(other*self.__den, self.__num)
- if isnum(other):
- return other / float(self)
- return NotImplemented
- __rdiv__ = __rtruediv__
- def __floordiv__(self, other):
- """Divide two Rats, returning the floored result."""
- if isint(other):
- other = Rat(other)
- elif not isRat(other):
- return NotImplemented
- x = self/other
- return x.__num // x.__den
- def __rfloordiv__(self, other):
- """Divide two Rats, returning the floored result (reversed args)."""
- x = other/self
- return x.__num // x.__den
- def __divmod__(self, other):
- """Divide two Rats, returning quotient and remainder."""
- if isint(other):
- other = Rat(other)
- elif not isRat(other):
- return NotImplemented
- x = self//other
- return (x, self - other * x)
- def __rdivmod__(self, other):
- """Divide two Rats, returning quotient and remainder (reversed args)."""
- if isint(other):
- other = Rat(other)
- elif not isRat(other):
- return NotImplemented
- return divmod(other, self)
- def __mod__(self, other):
- """Take one Rat modulo another."""
- return divmod(self, other)[1]
- def __rmod__(self, other):
- """Take one Rat modulo another (reversed args)."""
- return divmod(other, self)[1]
- def __eq__(self, other):
- """Compare two Rats for equality."""
- if isint(other):
- return self.__den == 1 and self.__num == other
- if isRat(other):
- return self.__num == other.__num and self.__den == other.__den
- if isnum(other):
- return float(self) == other
- return NotImplemented
- def __ne__(self, other):
- """Compare two Rats for inequality."""
- return not self == other
- # Silence Py3k warning
- __hash__ = None
- class RatTestCase(unittest.TestCase):
- """Unit tests for Rat class and its support utilities."""
- def test_gcd(self):
- self.assertEqual(gcd(10, 12), 2)
- self.assertEqual(gcd(10, 15), 5)
- self.assertEqual(gcd(10, 11), 1)
- self.assertEqual(gcd(100, 15), 5)
- self.assertEqual(gcd(-10, 2), -2)
- self.assertEqual(gcd(10, -2), 2)
- self.assertEqual(gcd(-10, -2), -2)
- for i in range(1, 20):
- for j in range(1, 20):
- self.assertTrue(gcd(i, j) > 0)
- self.assertTrue(gcd(-i, j) < 0)
- self.assertTrue(gcd(i, -j) > 0)
- self.assertTrue(gcd(-i, -j) < 0)
- def test_constructor(self):
- a = Rat(10, 15)
- self.assertEqual(a.num, 2)
- self.assertEqual(a.den, 3)
- a = Rat(10L, 15L)
- self.assertEqual(a.num, 2)
- self.assertEqual(a.den, 3)
- a = Rat(10, -15)
- self.assertEqual(a.num, -2)
- self.assertEqual(a.den, 3)
- a = Rat(-10, 15)
- self.assertEqual(a.num, -2)
- self.assertEqual(a.den, 3)
- a = Rat(-10, -15)
- self.assertEqual(a.num, 2)
- self.assertEqual(a.den, 3)
- a = Rat(7)
- self.assertEqual(a.num, 7)
- self.assertEqual(a.den, 1)
- try:
- a = Rat(1, 0)
- except ZeroDivisionError:
- pass
- else:
- self.fail("Rat(1, 0) didn't raise ZeroDivisionError")
- for bad in "0", 0.0, 0j, (), [], {}, None, Rat, unittest:
- try:
- a = Rat(bad)
- except TypeError:
- pass
- else:
- self.fail("Rat(%r) didn't raise TypeError" % bad)
- try:
- a = Rat(1, bad)
- except TypeError:
- pass
- else:
- self.fail("Rat(1, %r) didn't raise TypeError" % bad)
- def test_add(self):
- self.assertEqual(Rat(2, 3) + Rat(1, 3), 1)
- self.assertEqual(Rat(2, 3) + 1, Rat(5, 3))
- self.assertEqual(1 + Rat(2, 3), Rat(5, 3))
- self.assertEqual(1.0 + Rat(1, 2), 1.5)
- self.assertEqual(Rat(1, 2) + 1.0, 1.5)
- def test_sub(self):
- self.assertEqual(Rat(7, 2) - Rat(7, 5), Rat(21, 10))
- self.assertEqual(Rat(7, 5) - 1, Rat(2, 5))
- self.assertEqual(1 - Rat(3, 5), Rat(2, 5))
- self.assertEqual(Rat(3, 2) - 1.0, 0.5)
- self.assertEqual(1.0 - Rat(1, 2), 0.5)
- def test_mul(self):
- self.assertEqual(Rat(2, 3) * Rat(5, 7), Rat(10, 21))
- self.assertEqual(Rat(10, 3) * 3, 10)
- self.assertEqual(3 * Rat(10, 3), 10)
- self.assertEqual(Rat(10, 5) * 0.5, 1.0)
- self.assertEqual(0.5 * Rat(10, 5), 1.0)
- def test_div(self):
- self.assertEqual(Rat(10, 3) / Rat(5, 7), Rat(14, 3))
- self.assertEqual(Rat(10, 3) / 3, Rat(10, 9))
- self.assertEqual(2 / Rat(5), Rat(2, 5))
- self.assertEqual(3.0 * Rat(1, 2), 1.5)
- self.assertEqual(Rat(1, 2) * 3.0, 1.5)
- def test_floordiv(self):
- self.assertEqual(Rat(10) // Rat(4), 2)
- self.assertEqual(Rat(10, 3) // Rat(4, 3), 2)
- self.assertEqual(Rat(10) // 4, 2)
- self.assertEqual(10 // Rat(4), 2)
- def test_eq(self):
- self.assertEqual(Rat(10), Rat(20, 2))
- self.assertEqual(Rat(10), 10)
- self.assertEqual(10, Rat(10))
- self.assertEqual(Rat(10), 10.0)
- self.assertEqual(10.0, Rat(10))
- def test_future_div(self):
- exec future_test
- # XXX Ran out of steam; TO DO: divmod, div, future division
- future_test = """
- from __future__ import division
- self.assertEqual(Rat(10, 3) / Rat(5, 7), Rat(14, 3))
- self.assertEqual(Rat(10, 3) / 3, Rat(10, 9))
- self.assertEqual(2 / Rat(5), Rat(2, 5))
- self.assertEqual(3.0 * Rat(1, 2), 1.5)
- self.assertEqual(Rat(1, 2) * 3.0, 1.5)
- self.assertEqual(eval('1/2'), 0.5)
- """
- def test_main():
- test_support.run_unittest(RatTestCase)
- if __name__ == "__main__":
- test_main()
|