Fix wrong integer division where rounding up was intended #1254
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simogasp
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I've updated the function again. I managed to leave an error for negative numbers and ran missed it by running tests that haven't yet been recompiled with updated code. |
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it's funny how an apparently simple function like this still has so many entries on StackOverflow and many different answers. |
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fabiencastan
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The intention here likely was to get floating-point division result and round it upwards. However, the division was performed with integer arguments, fractional part was lost and thus std::ceil did nothing.
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The intention in cases like
std::ceil(a / b)(whereaandbare integers) likely was to get floating-point division result and round it upwards. However, the division was performed with integer arguments, fractional part was lost and thusstd::ceildid nothing. This PR introduces a separate function to perform such integer division and fixes the buggy cases.If the original intention was wrong, this PR will break behavior. According to my limited understanding of the code the original intention was correct.
A subsequent PR will change all similar cases where we currently do
int(std::ceil(double(a) / double(b)))to usedivideRoundUp().