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Author Topic: 11.3 Epsilon necessary in compare method? (Read 1408 times)
theconnorpower
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on: October 14, 2010, 02:27:37 AM

I thought it was always best practice to compare using an epsilon when comparing float values in C. Am I wrong? No one else seems to have implemented this approach. Example below.

Code: (Objective-C)
-(int) compare: (Fraction *)f
{
double selfNum = [self convertToNum];
double fNum = [f convertToNum];

if (fabs(selfNum - fNum) < DBL_EPSILON)
return 0;
else if (selfNum > fNum)
return 1;
else
return -1;
}
Last Edit: October 15, 2010, 02:25:11 PM by theconnorpower Logged
theconnorpower
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Reply #1 on: October 24, 2010, 06:37:02 PM

Bumpitty bump?
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skochan
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Reply #2 on: October 24, 2010, 09:17:17 PM

Yeah, I do think it's a good idea to compare floats against some epsilon due to the inherent inaccuracy of representing floating point numbers.

Cheers,

Steve
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theconnorpower
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Reply #3 on: October 24, 2010, 09:23:49 PM

Awesome.

Thanks Steve.
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