134
How Python Compares Floats and Ints: When Equals Isn’t Really Equal
(blog.codingconfessions.com)
this post was submitted on 27 May 2024
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I dont think comparisons should be doing type conversion if i compare a float to an int i want it to say false cos types are different.
I don't think that's how most programmers expect it to work at all.
However most people would also expect 0.1+0.2==0.3 to return true, so what do I know.
Floating point is something most of us ignore until it bites us in the ass. And then we never trust it again.
I have to admit: If you (semi-)regularly use floating point comparisons in programming, I don't know why you would ever expect 0.1 + 0.2 == 0.3 to return true. It's common practice to check
abs(a - b) < tol, wheretolis some small number, to the point that common unit-testing libraries have built-in methods likeassertEqual(a, b, tol)specifically for checking whether floats are "equal".Yeah, a lot of editors throw warnings for using the equals operator with floats by default, as far as I know it's considered bad practice to do it that way.