Is there a better way to test if a double has decimal digits than this?
double value = 7.2;
bool isInt = value == double(round(value));
BTW: I use C++ 11 and gcc AND MSVC2015
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Jonathan Hall
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Marcus
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Better in terms of what? – Jabberwocky Aug 23 '18 at 07:59
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The problem with floating point numbers is that what you think is `9.0` (for example) might actually not be. See [Is floating point math broken?](https://stackoverflow.com/questions/588004/is-floating-point-math-broken) for some details. – Some programmer dude Aug 23 '18 at 08:00
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This is why i ask. I think it won't work for every number. But i can't figure out which one – Marcus Aug 23 '18 at 08:01
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Just to highlight points from the duplicate: [`modf`](https://en.cppreference.com/w/cpp/numeric/math/modf), [`trunc`](https://en.cppreference.com/w/cpp/numeric/math/trunc). – BoBTFish Aug 23 '18 at 08:01
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thx, i use the solution from the other question. – Marcus Aug 23 '18 at 08:04