Can someone clarify to me please why past2 is NOT negative when this code is run? Even though past is.
Thanks.
NSTimeInterval p1 = (arc4random()%600000);
NSTimeInterval past = -p1;
NSTimeInterval past2 = -(arc4random()%600000);
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WalterF
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7Search a definition for Random... – Sandro Meier Aug 30 '11 at 12:08
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Can you clarify us why do you use `arc4random()`? – EmptyStack Aug 30 '11 at 12:10
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sorry, I meant something different. I edited the question now. – WalterF Aug 31 '11 at 13:41
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The is a completely different question compared to the original. You might want to post edits in a way that the history is clear. Particularly when answers have been obsoleted. In my opinion. – steenhulthin Aug 31 '11 at 17:29
1 Answers
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arc4random() returns an unsigned int (u_int32_t), so trying to make it negative is coercing the result to unsigned as well, which is why you're getting a very large positive number instead of a negative number.
If you want to get a negative random result in one call, try:
NSTimeInterval past2 = - (int) (arc4random()%600000);
joe
Flyingdiver
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