mirror of
https://github.com/ruby/ruby.git
synced 2022-11-09 12:17:21 -05:00
72 lines
2.4 KiB
Ruby
72 lines
2.4 KiB
Ruby
require 'bigdecimal'
|
|
|
|
describe :bigdecimal_power, shared: true do
|
|
it "powers of self" do
|
|
e3_minus = BigDecimal("3E-20001")
|
|
e3_minus_power_2 = BigDecimal("9E-40002")
|
|
e3_plus = BigDecimal("3E20001")
|
|
e2_plus = BigDecimal("2E40001")
|
|
e5_minus = BigDecimal("5E-40002")
|
|
e = BigDecimal("1.00000000000000000000123456789")
|
|
one = BigDecimal("1")
|
|
ten = BigDecimal("10")
|
|
# The tolerance is dependent upon the size of BASE_FIG
|
|
tolerance = BigDecimal("1E-70")
|
|
ten_powers = BigDecimal("1E10000")
|
|
pi = BigDecimal("3.14159265358979")
|
|
e3_minus.send(@method, 2).should == e3_minus_power_2
|
|
e3_plus.send(@method, 0).should == 1
|
|
e3_minus.send(@method, 1).should == e3_minus
|
|
e2_plus.send(@method, -1).should == e5_minus
|
|
e2_plus.send(@method, -1).should == e5_minus.power(1)
|
|
(e2_plus.send(@method, -1) * e5_minus.send(@method, -1)).should == 1
|
|
e.send(@method, 2).should == e * e
|
|
e.send(@method, -1).should be_close(one.div(e, 120), tolerance)
|
|
ten.send(@method, 10000).should == ten_powers
|
|
pi.send(@method, 10).should be_close(Math::PI ** 10, TOLERANCE)
|
|
end
|
|
|
|
it "powers of 1 equal 1" do
|
|
one = BigDecimal("1")
|
|
one.send(@method, 0).should == 1
|
|
one.send(@method, 1).should == 1
|
|
one.send(@method, 10).should == 1
|
|
one.send(@method, -10).should == 1
|
|
end
|
|
|
|
it "0 to power of 0 is 1" do
|
|
zero = BigDecimal("0")
|
|
zero.send(@method, 0).should == 1
|
|
end
|
|
|
|
it "0 to powers < 0 is Infinity" do
|
|
zero = BigDecimal("0")
|
|
infinity = BigDecimal("Infinity")
|
|
zero.send(@method, -10).should == infinity
|
|
zero.send(@method, -1).should == infinity
|
|
end
|
|
|
|
it "other powers of 0 are 0" do
|
|
zero = BigDecimal("0")
|
|
zero.send(@method, 1).should == 0
|
|
zero.send(@method, 10).should == 0
|
|
end
|
|
|
|
it "returns NaN if self is NaN" do
|
|
BigDecimal("NaN").send(@method, -5).should.nan?
|
|
BigDecimal("NaN").send(@method, 5).should.nan?
|
|
end
|
|
|
|
it "returns 0.0 if self is infinite and argument is negative" do
|
|
BigDecimal("Infinity").send(@method, -5).should == 0
|
|
BigDecimal("-Infinity").send(@method, -5).should == 0
|
|
end
|
|
|
|
it "returns infinite if self is infinite and argument is positive" do
|
|
infinity = BigDecimal("Infinity")
|
|
BigDecimal("Infinity").send(@method, 4).should == infinity
|
|
BigDecimal("-Infinity").send(@method, 4).should == infinity
|
|
BigDecimal("Infinity").send(@method, 5).should == infinity
|
|
BigDecimal("-Infinity").send(@method, 5).should == -infinity
|
|
end
|
|
end
|