iphone float vs integer rounding?

Posted by Rob on Stack Overflow See other posts from Stack Overflow or by Rob
Published on 2010-06-17T17:24:28Z Indexed on 2010/06/17 17:33 UTC
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Okay, from what I understand, an integer that is a fraction will be rounded one way or the other so that if a formula comes up with say 5/6 - it will automatically round it to 1. I have a calculation:

xyz = ((1300 - [abc intValue])/6) + 100;

xyz is defined as an NSInteger, abc is an NSString that is chosen via a UIPicker. I want the calculation (1300 - [abc intValue]) to add 1 to 100 for each 6 units below 1300. For example, 1255 should result in xyz having a value of 100 and 1254 should result in a value of 101.

Now, I understand that my formula above is wrong because of the rounding principles, but I am getting some CRAZY results from the program itself. When I punched in 1259 - I got 106. When I punched in 1255 - I got 107. Why would it behave that way?

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