cool! i forgot all about x&(x-1) !! now i can use it to improve my AI
Computer Science Canada comparing double to integer |
| Author: | cool dude [ Sun Aug 13, 2006 2:18 pm ] |
| Post subject: | comparing double to integer |
how would i compare a number that is declared as a double although it is an integer that just has a zero at the end. ex: 123.0 to an integer. i can't declare the double number as an integer because i'm using Math.Pow and it always makes it double, but i wanna take the answer from that and see if it equals to an integer number. for example does 123.0 = 123. this will not be equal, thus i will not get any results. any suggestions? |
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| Author: | Justin_ [ Sun Aug 13, 2006 2:49 pm ] |
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Have you tried: instead of casting the Math.Pow variable cast the integer you are comparing to a float? Just a suggestion. (Math.Pow.float_int == (float) int_variable) |
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| Author: | Justin_ [ Sun Aug 13, 2006 2:52 pm ] |
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Or wait, I misunderstood. Just cast the double returned from Math.Pow and compare... if ((int) power_returned == int_) |
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| Author: | wtd [ Sun Aug 13, 2006 2:56 pm ] |
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Keep in mind that floating point numbers are inherently imprecise. Thus it can be difficult to directly compare two such numbers for equality. |
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| Author: | r.3volved [ Sun Aug 13, 2006 4:47 pm ] |
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also, casting a double to an int will either truncate the decimals or round them... You would have to cast your integer to a double to compare the two, not visa versa |
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| Author: | bugzpodder [ Sat Sep 16, 2006 8:12 pm ] |
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add some epsilon constant to the result and truncate it by casting to an int |
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| Author: | McKenzie [ Tue Sep 19, 2006 11:54 am ] |
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Floating point numbers are imprecise only when representing fractions, or extreamely large numbers. Casting it should be fine. |
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| Author: | bugzpodder [ Thu Sep 21, 2006 7:06 pm ] |
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http://www.topcoder.com/tc?module=Static&d1=tutorials&d2=integersReals |
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| Author: | bugzpodder [ Thu Sep 21, 2006 7:11 pm ] |
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cool! i forgot all about x&(x-1) !! now i can use it to improve my AI |
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