Why does javascript math operations produce different results than python? and how to fix it?
python:
>> 4-((4/3)*3)+1
>> 2
javascript:
>> 4-((4/3)*3)+1
>> 1
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pyhton 3 returns 1.0 / Pyhton 2 returns 2, so the diff is between python- 2 and 3 – Ari Gold Dec 08 '16 at 13:13
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even without parentheses, it is in js 1. – Nina Scholz Dec 08 '16 at 13:15
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In python, `4/3` will return `1` and not `1.33` – Rajesh Dec 08 '16 at 13:15
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This might help: http://stackoverflow.com/questions/1267869/how-can-i-force-division-to-be-floating-point-in-python-division-keeps-rounding – Rajesh Dec 08 '16 at 13:18
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2Arguably the *Python math* "isn't working" here… – deceze Dec 08 '16 at 13:18
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If you want floor division in JavaScript you need to use `Math.floor`, as shown here: http://stackoverflow.com/questions/4228356/integer-division-in-javascript – PM 2Ring Dec 08 '16 at 13:20
2 Answers
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In python, 4/3 == 1, since it is an an integer operation. In JS it is a floating point operation, and therefore 4/3 === 1.3333333333333333.
If you want floating point operations in python, have floating point in the equation. E.g.
4-((4/3)*3)+1 == 2 (Integer)
4-((4.0/3.0)*3)+1 == 1 (Float)
MoeSattler
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It's even better to do `from __future__ import division` to force Python 2 to do float division. – PM 2Ring Dec 08 '16 at 13:18
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Tip for especially lazy readers like myself: you only need one argument to be a float to get floating point division, and a float literal can end with a decimal point, so you can accomplish this by just adding a single dot: `4-((4./3)*3)+1` – Kevin Dec 08 '16 at 13:27
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Actually javascript produces decimal values of 1.333333 for 4/3 and it multiplied with 3 which tends to produce 4. 1 is the correct result for 4-((4/3)*3)+1 but if you want 2 as your result then you need to parse the value of 4/3 to int so 1.333333 will become 1 which is multiplied with 3 will produce 3.
alert(4-(parseInt(4/3)*3)+1)
vijay
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