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# File 'lib/kgl/kmath.rb', line 141
def to_r
a = self.abs
q = a.to_r_exact
s = (self < 0.0) ? -1 : 1
if q.denominator < q.numerator
l = [q.numerator.div(q.denominator), 1]
r = Rational(*l)
return r*s if r.to_f == a
h = [l[0]+1, 1]
r = Rational(*h)
return r*s if r.to_f == a
else
h = [1, q.denominator.div(q.numerator)]
r = Rational(*h)
return r*s if r.to_f == a
l = [1, h[1]+1]
r = Rational(*l)
return r*s if r.to_f == a
end
loop do
m = [l[0]+h[0], l[1]+h[1]]
r = Rational(*m)
if r.to_f == a
return r*s
elsif r < q
l = m
else
h = m
end
end
end
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