How to round off decimal number to 2 digits in iphone?

Question

How can we round off decimal numbers to 2 digits in iphone ?

For example ,

1. 5345 --> 53

2. 570 -- > 57

3. 89523 -- > 90

I tried to use nsformatter for this and here is the code i used ,

    NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
[formatter setNumberStyle:NSNumberFormatterDecimalStyle];
[formatter setMaximumIntegerDigits:2];
[formatter setRoundingMode: NSNumberFormatterRoundUp];

NSString *numberString = [formatter stringFromNumber:[NSNumber numberWithInt:570]];

    [formatter release];
    NSLog(@"%@",numberstring);

I keep on getting the value as 70 even after changing the rounding mode to different options. Please help me with this

Thanks, Vinod.

Answer 1

Use this simple code instead of formatter;

myFloat = roundf(100 * myFloat) / 100.0;

i hope it helps.

Or you can use this

float roundedValue = round(2.0f * number) / 2.0f;
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init]; 
[formatter setMaximumFractionDigits:2]; 
[formatter setRoundingMode: NSNumberFormatterRoundDown];  
NSString *numberString = [formatter stringFromNumber:[NSNumber numberWithFloat:roundedValue]]; 
[formatter release];

Answer 2

Since you're looking to round up the decimal digits, you should actually provide a float for this and set the maximum fractional digits to 2. You're probably looking for this,

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
[formatter setNumberStyle:NSNumberFormatterDecimalStyle];
[formatter setMaximumFractionDigits:2];
[formatter setRoundingMode: NSNumberFormatterRoundHalfUp];

NSString *numberString = [formatter stringFromNumber:[NSNumber numberWithFloat:570.57018]];

[formatter release];
NSLog(@"%@",numberString);