How to trim zeros after decimal point

Question

I am trying to trim zeros after a decimal point as below but it\'s not giving desired result.

trig = [currentVal doubleValue];
trig = trig/100;
NSNumberForma         


        

Answer 1

From the documentation, it looks like setFractionDigits: is only for converting the other way.

The best thing to do is probably to convert your number to an integer before formatting it e.g.

 double converted = round(trig); // man round for docs

You can use also the formatting functions of stringWithFormat: of NSString, but then you will lose all the localisation advantages you get with NSNumberFormatter.

Answer 2

This may not be a proper solution where there is NSNumberFormetter Class, But I just did this rather then googling a lot! ;)

Here is an example, if it helps:

-(NSString*) trimZerosAfterDecimalPoint:(NSString*)string_ {

    double doubleValue=[string_ doubleValue];    
    long   leftPart=(long)doubleValue;
    double rightPart=doubleValue-(double)leftPart;

    NSString *rightPartAsStr=[NSString stringWithFormat:@"%f", rightPart];

    int i=0;
    for (i=rightPartAsStr.length-1; i>=2; i--) {
        if ([rightPartAsStr characterAtIndex:i]!='0') {            
            rightPartAsStr=[rightPartAsStr substringWithRange:NSMakeRange(2, i-1)];
            break;
        }
    }

    if (i<2) {
        string_=[NSString stringWithFormat:@"%ld", leftPart];
    } else {
        string_=[NSString stringWithFormat:@"%ld.%@", leftPart, rightPartAsStr];
    }

    return string_;
}

Answer 3

I just had to do this for one of my programs and heres how I went about it:

- (void) simplify{
        int length = (int)[self.calcString length];
        for (int i = (int)[self.calcString length]; i > 0; i--) {
            if  ([self.calcString rangeOfString:@"."].location != NSNotFound) {
                NSRange prevChar = NSMakeRange(i-1, 1);
                if ([[self.calcString substringWithRange:prevChar] isEqualToString:@"0"]||
                    [[self.calcString substringWithRange:prevChar] isEqualToString:@"."]) 
                    length--;
                else
                    break;
        }
        self.calcString = [self.calcString substringToIndex:length];
    }
}

Answer 4

This works

display.text = [@(trig) stringValue];

Answer 5

it is because of your datatype cannot be formatted is such a manner.

Answer 6

In case this helps someone. I wanted 1 decimal value but no '.0' on the end if the float was '1.0'. Using %g would give scientific notation for longer numbers, following ugliness worked well enough for me as high accuracy wasn't critical.

// Convert to 1 dp string,
NSString* dirtyString = [NSString stringWithFormat: @"%.1f", self.myFloat];

// Convert back to float that is now a maximum of 1 dp,
float myDirtyFloat = [dirtyString floatValue];

// Output the float subtracting the zeros the previous step attached
return [NSString stringWithFormat: @"%g", myDirtyFloat];