Formatting numbers

Posted by Jan Vantomme on 30 January 2009.

This one is just a quick tip on presenting decimal numbers on a label or logging them to the console. In my last article on using NSLog, I wrote about using format specifiers like %f, %i and %@ to log variables to the console.

If you use %f to display or log a float, you will always see the full number. If you use the format specifier %.2f, the number will be shortened with only two decimal digits.

float myNumber 134.65987239;
NSLog(@"This is a decimal number: %f"myNumber);
NSLog(@"This is a decimal number: %.2f"myNumber);
myLabel.text [NSString stringWithFormat:@"%.2f"myNumber]

This code example will print these two lines to the console:

This is a decimal number134.65987239
This is a decimal number

The last line of the code example will also set the text of myLabel to 134.66

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