In my project, want to show the weather in fahrenheit first, then if the user wants clickes on conversion, needs to show the weather in celsius. My code is

NSNumber *metric = [[NSUserDefaults standardUserDefaults] objectForKey:@"metric"];

NSLog(@"Metric is %@", metric);

CGFloat aFloat = [speed floatValue];
CGFloat tFloat = [temperature floatValue];
CGFloat tempFloat = (tFloat-30)/2;
NSNumber * p_Number = [NSNumber numberWithFloat:tempFloat];


//Convert mph to kmph
if ([metric boolValue]) {

    [windValueLabel setText:[NSString stringWithFormat:@"%.2f kmph", aFloat * 1.6]  ];
    temperatureLabel.text = [NSString stringWithFormat:@"%@", p_Number];

}
else{
    [windValueLabel setText:[NSString stringWithFormat:@"%.2f mph", aFloat / 1.6]];
    temperatureLabel.text = [NSString stringWithFormat:@"%@", temperature];
}

When u start the app, its working and showing temperature in fahrenheit, but crashes at celsius man... is that the current conversion. help me out guys