ruby--ruby/test/ruby/test_float.rb

require 'test/unit'

class TestFloat < Test::Unit::TestCase
  def test_float
    assert_equal(2, 2.6.floor)
    assert_equal(-3, (-2.6).floor)
    assert_equal(3, 2.6.ceil)
    assert_equal(-2, (-2.6).ceil)
    assert_equal(2, 2.6.truncate)
    assert_equal(-2, (-2.6).truncate)
    assert_equal(3, 2.6.round)
    assert_equal(-2, (-2.4).truncate)
    assert((13.4 % 1 - 0.4).abs < 0.0001)
  end

  def nan_test(x,y)
    extend Test::Unit::Assertions
    assert(x != y)
    assert_equal(false, (x < y))
    assert_equal(false, (x > y))
    assert_equal(false, (x <= y))
    assert_equal(false, (x >= y))
  end
  def test_nan
    nan = 0.0/0
    nan_test(nan, nan)
    nan_test(nan, 0)
    nan_test(nan, 1)
    nan_test(nan, -1)
    nan_test(nan, 1000)
    nan_test(nan, -1000)
    nan_test(nan, 1_000_000_000_000)
    nan_test(nan, -1_000_000_000_000)
    nan_test(nan, 100.0);
    nan_test(nan, -100.0);
    nan_test(nan, 0.001);
    nan_test(nan, -0.001);
    nan_test(nan, 1.0/0);
    nan_test(nan, -1.0/0);
  end

  def test_precision
    #s = "3.7517675036461267e+17"
    #assert(s == sprintf("%.16e", s.to_f))
    f = 3.7517675036461267e+17
    assert_equal(f, sprintf("%.16e", f).to_f)
  end
end