As in most languages the format is
%.2f
you can see more examples here
Edit: I also got this if your concerned about the display of the point in cases of 25.00
{
NSNumberFormatter *fmt = [[NSNumberFormatter alloc] init];
[fmt setPositiveFormat:@"0.##"];
NSLog(@"%@", [fmt stringFromNumber:[NSNumber numberWithFloat:25.342]]);
NSLog(@"%@", [fmt stringFromNumber:[NSNumber numberWithFloat:25.3]]);
NSLog(@"%@", [fmt stringFromNumber:[NSNumber numberWithFloat:25.0]]);
}
2010-08-22 15:04:10.614 a.out[6954:903] 25.34
2010-08-22 15:04:10.616 a.out[6954:903] 25.3
2010-08-22 15:04:10.617 a.out[6954:903] 25
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