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+--- Thread: Why 7%1.4 is not zero? (/thread-2308.html)
Why 7%1.4 is not zero? - tinghf - Mar-06-2017
Hello guys,
7/1.4=5, the remainder is zero, simple maths.
But why 7%1.4 gives the result 4.440892098500626e-16?
I know it is extremely close to zero, but I want to know how Python do the maths and why it happen.
Does anyone can help me?
p.s. I am using Python 2.7.13
RE: Why 7%1.4 is not zero? - micseydel - Mar-06-2017
It's because the underlying math is done in binary. Consider 10 / 3, you can't represent it precisely with decimal notation. The same problem happens here, except that 1.4 can't be precisely in binary.
If it's a problem in your code, the typical way to solve the problem is to have a tolerance. Check that the result is sufficiently small. 10**(-16) is very small.
RE: Why 7%1.4 is not zero? - tinghf - Mar-07-2017
(Mar-06-2017, 07:14 PM)micseydel Wrote: It's because the underlying math is done in binary. Consider 10 / 3, you can't represent it precisely with decimal notation. The same problem happens here, except that 1.4 can't be precisely in binary.
If it's a problem in your code, the typical way to solve the problem is to have a tolerance. Check that the result is sufficiently small. 10**(-16) is very small.
Thank you! Got it!