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pythonfractions

How does one simplify a complicated ratio?

Is there a simple way to simplify a ratio down? For example 1875:5625:625 would become 3:9:1.

I am using Python, but I'd like to know why and not just how.

Solution

  • Edit: Please note that fractions.gcd has been Deprecated since Python 3.5: Use math.gcd() instead.

    There's a built-in gcd function in the fractions module so utilizing it I was able to get decent output:

    from fractions import gcd

ratio = '1875:5625:625'

def solve(ratio):
    numbers = [int(i) for i in ratio.split(':')]
    denominater = reduce(gcd,numbers)
    solved = [i/denominater for i in numbers]
    return ':'.join(str(i) for i in solved)

ratio_2_solve =  solve(ratio)
print ratio_2_solve
#3:9:1

    So given the ratio 

    1875:5625:625

    It would produce : 

    3:9:1

    But that's not the best part of it, you could even put ratios like:

    '1875:5625:625:5000:46875:46250'

    And still get the output of:

    3:9:1:8:75:74