When I do this:
NSLog(@"%i",1.5 - 1.00 == 0.5);
I get 1, but when I do this:
NSLog(@"%i",1.33 - 1.00 == 0.33);
I get 0.
Is there any way to get around this?
When I do this: NSLog(@%i,1.5 – 1.00 == 0.5); I get 1, but when
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When I do this:
NSLog(@"%i",1.5 - 1.00 == 0.5);
I get 1, but when I do this:
NSLog(@"%i",1.33 - 1.00 == 0.33);
I get 0.
Is there any way to get around this?
The problem is with the precision of floating-point calculations: you should generally avoid comparing floats and double-precision numbers for equality using
==operator, preferring a check for the difference to be smaller than a tiny epsilon (e.g.1E-9).The first example works because the numbers are composed of powers of 2:
1 = 2^0, and0.5 = 2^-1. The numbers from the second example cannot be decomposed as powers of 2 exactly, so the equality check does not work.