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i'm using gambit-c intepreter to evaluate scheme arithmetic operations, but it's results are bit off. for example i execute (+ 23 20.01) and it gives me 43.010000000000005, instead of 43.01.

This only occurs if i use numbers with 2 decimal points.

Is there a fix for this?

user3533844
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1 Answers1

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It has to do with how floating point calculations are done. Please read What Every Programmer Should Know About Floating-Point Arithmetic.

You are in luck! In Scheme you fix this by using exact numbers: 

(+ 23 #e20.01) ; ==> 4301/100

You can make it inexact with:

(exact->inexact (+ 23 #e20.01)) ; ==> 43.01
Sylwester
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