sympy/core/tests/test_evalf.py

   1 from sympy import *
   2 import py
   3 import decimal
   4
   5 x = Symbol('x')
   6
   7 def eq(a,b):
   8     t = decimal.Decimal("0.00000000000000001")
   9     return -t < a-b < t
  10
  11 def _test_evalf():
  12     e = log(3)/log(2)-1
  13     assert eq(e.evalf(), decimal.Decimal("0.58496250072115618145373"))
  14
  15     # XXX No errors raised for this
  16     f = 2*x+2
  17     py.test.raises(ValueError, f.evalf)
  18
  19     # XXX This assumption no longer raised
  20     e = sqrt(Rational(2)+1)/3
  21     assert e.is_number
  22
  23 def test_bug1():
  24     x = Symbol('x')
  25     y = x*x
  26     assert eq(y.subs(x, Real(3.0)).evalf(), 9)
  27
  28 def test_bug2():
  29     a = Real(4.)
  30     x = a + a