Implement Complex#abs in terms of Math.hypot
Math.hypot avoids premature overflow and underflow
MODIFY
mrbgems/mruby-complex/mrblib/complex.rb
mrbgems/mruby-complex/mrblib/complex.rb
@@ -62,7 +62,7 @@ class Complex < Numeric
end
def abs
- Math.sqrt(abs2)
+ Math.hypot imaginary, real
end
alias_method :magnitude, :abs

MODIFY
mrbgems/mruby-complex/test/complex.rb
mrbgems/mruby-complex/test/complex.rb
@@ -70,6 +70,14 @@ end
assert 'Complex#abs' do
assert_float Complex(-1).abs, 1
assert_float Complex(3.0, -4.0).abs, 5.0
+ if 1e39.infinite? then
+ # MRB_USE_FLOAT in effect
+ exp = 125
+ else
+ exp = 1021
+ end
+ assert_true Complex(3.0*2**exp, 4.0*2**exp).abs.finite?
+ assert_float Complex(3.0*2**exp, 4.0*2**exp).abs, 5.0*2**exp
end
assert 'Complex#abs2' do

Implement Complex#abs in terms of Math.hypot

Math.hypot avoids premature overflow and underflow