flaot -double comparison
I m getting equal as output...
My doubt is float compared with double in if statement,
then it should b unequal right??
Is it something like type conversion?? I want just to clarify this point..
Code:int main() { float a=7.0; //6.9999999 a=a+0.0000001;// 7.0f if(a==7.0) printf("equal"); else printf("unequal"); getchar(); }
Floating point values (with rare exceptions) can not be compared for equality with constants (or values derived from constants other than those making up the original number). In general, comparing floating point for "is this equal to that" should really be done as "delta" comparisons, e.g.Code:if (fabs(a-b) < 0.000001) printf("equal"); else printf("not equal");
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Mats
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i hope these links will help u
http://c-faq.com/fp/
http://www.cygnus-software.com/paper...ringfloats.htm
I think the constant you compare to is called epsilon.Originally Posted by matsp
QuantumPete
Last edited by QuantumPete; 02-24-2009 at 03:37 PM.
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A float cannot distinguish 7.0000001 from 7 because it does not have enough significant bits to do so. The range of magnitudes of those numbers is too great.
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