CODEWITHSUNDEEP
objective-cxcode4
Java Ka Baby
Java Ka Baby

Reputation: 4920

How to compare doubles in Objective C?

I have following method which is failing . I think I am comparing double with int but do know the best approach.

-(BOOL)isValidCoordinate:(CLLocationCoordinate2D)coordinate
{
   //Always fail first condition here.
    if (coordinate.latitude > -90 && coordinate.latitude< 90) {
        [NSException raise:@"Invalid latitude value" format:@"Latitude of %d is invalid", coordinate.latitude];
    }

    if (coordinate.longitude > -180 && coordinate.longitude < 180) {
        [NSException raise:@"Invalid longitude value" format:@"Longitude of %d is invalid", coordinate.longitude]; 
    }

    [NSException raise:@"Invalid longitude value blash " format:@"Longitude of %d is invalid asd", coordinate.longitude]; 
    return TRUE;
}

Upvotes: 0

Views: 1136

Answers (3)

FormigaNinja
FormigaNinja

Reputation: 1571

In this case, you don't need to check lat/long explicitly since MapKit has a method that do this to you. Try the following:

if (!CLLocationCoordinate2DIsValid(coordinate)) {

    [NSException raise:@"Invalid coordinate values" format:@"Latitude: %f Longitude: %f", coordinate.latitude, coordinate.longitude];
}

Upvotes: 0

Stephen Darlington
Stephen Darlington

Reputation: 52575

Your comparison should work. The compiler will convert the integer to a floating point number before comparing. If you want to be sure you can change it to:

if (coordinate.latitude > -90.0 && coordinate.latitude< 90.0)

But your main problem, I think, is that you're reporting the wrong numbers. %d in a format string tells it to print an integer. You need to tell it to output a floating point number:

[NSException raise:@"Invalid latitude value" format:@"Latitude of %f is invalid", coordinate.latitude];

Upvotes: 2

Fred Foo
Fred Foo

Reputation: 363848

The problem is not in the comparison.

if (coordinate.latitude > -90 && coordinate.latitude < 90)
    [NSException raise:@"Invalid latitude value"
                 format:@"Latitude of %d is invalid", coordinate.latitude];

should raise an exception for -30.99986 by the logic of this code, since it's between -90 and 90. The problem is the %d you use to format the error message, which regards its argument as int and gives you strange results.

Upvotes: 1

Related Questions