require File.expand_path('../../fixtures/classes', __FILE__) describe :complex_math_acosh, :shared => true do it "returns the principle value of the inverse hyperbolic cosine of the argument" do @object.send(:acosh, 14.2).should be_close(3.345146999647, TOLERANCE) @object.send(:acosh, 1.0).should be_close(0.0, TOLERANCE) end it "returns the principle value of the inverse hyperbolic cosine for numbers less than 1.0 as a Complex number" do @object.send(:acosh, 1.0 - TOLERANCE).should be_close(Complex(0.0, 0.00774598605746135), TOLERANCE) @object.send(:acosh, 0).should be_close(Complex(0.0, 1.5707963267949), TOLERANCE) @object.send(:acosh, -1.0).should be_close(Complex(0.0, 3.14159265358979), TOLERANCE) end it "returns the principle value of the inverse hyperbolic cosine for Complex numbers" do @object.send(:acosh, Complex(3, 4)) @object.send(:acosh, Complex(3, 4)).image.should be_close(0.93681246115572, TOLERANCE) @object.send(:acosh, Complex(3, 4)).real.should be_close(2.305509031243477, TOLERANCE) end end describe :complex_math_acosh_bang, :shared => true do it "returns the principle value of the inverse hyperbolic cosine of the argument" do @object.send(:acosh!, 14.2).should be_close(3.345146999647, TOLERANCE) @object.send(:acosh!, 1.0).should be_close(0.0, TOLERANCE) end it "raises Errno::EDOM for numbers less than 1.0" do lambda { @object.send(:acosh!, 1.0 - TOLERANCE) }.should raise_error(Errno::EDOM) lambda { @object.send(:acosh!, 0) }.should raise_error(Errno::EDOM) lambda { @object.send(:acosh!, -1.0) }.should raise_error(Errno::EDOM) end it "raises a TypeError when passed a Complex number" do lambda { @object.send(:acosh!, Complex(4, 5)) }.should raise_error(TypeError) end end