About NSNumber numberWithDouble

Question

double test1 = 5.58f;

NSString *test2 = @"5.58";

NSLog(@"%@", [NSNumber numberWithDouble:test1]);

NSLog(@"%@", [NSNumber numberWithDouble:[test2 doubleValue]]);

Output:

5.579999923706055

5.58

Why the convert is difference?

Answer 1

Probably due to the fact that 5.58f is a float, not a double.