Complex numbers division error

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Guess is complex number math goes wrong in some cases:

require "complex"

c1 = Complex.new 1, 0
c2 = Complex.new -1, 0

p c1 / c2 # => (NaN + NaNi)

(Nani?) :))

Actual result should be (-1 + 0i).

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Translated from npm package:

def /( other : Complex ) : Complex
	if zero? && other.zero? || abs2 == Float64::INFINITY && other.abs2 == Float64::INFINITY
		return Complex.new Float64::NAN, Float64::NAN
	end

	if abs2 == Float64::INFINITY || other.zero?
		return Complex.new Float64::INFINITY, Float64::INFINITY
	end

	if zero? || other.abs2 == Float64::INFINITY
		return Complex.zero
	end

	if other.imag.zero?
		return Complex.new real / other.real, imag / other.real
	end

	if other.real.abs < other.imag.abs
		m = other.real / other.imag
		n = other.real * m + other.imag
		Complex.new ( real * m + imag ) / n, ( imag * m - real ) / n
	else
		m = other.imag / other.real
		n = other.imag * m + other.real
		Complex.new ( real + imag * m ) / n, ( imag - real * m ) / n
	end
end

That works well.

[SlayerShadow]

At least

crystal/src/complex.cr

Line 240 in dacd97b

if other.real <= other.imag

- this line (if other.real <= other.imag) should include abs for real and image, other logic looks the same.