Ilya  Nikiforov Ilya Nikiforov - 2 months ago 6
Ruby Question

Turning long fixed number to array Ruby

Is there a method in ruby to turn fixnum like 74239 into an array like [7,4,2,3,9]?

Answer

You don't need to take a round trip through string-land for this sort of thing:

def digits(n)
    Math.log10(n).floor.downto(0).map { |i| (n / 10**i) % 10 }
end

ary = digits(74239)
# [7, 4, 2, 3, 9]

This does assume that n is positive of course, slipping an n = n.abs into the mix can take care of that if needed. If you need to cover non-positive values, then:

def digits(n)
    return [0] if(n == 0)
    if(n < 0)
       neg = true
       n   = n.abs
    end
    a = Math.log10(n).floor.downto(0).map { |i| (n / 10**i) % 10 }
    a[0] *= -1 if(neg)
    a
end
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