What is the range of a double in Objective-C?

Question

I have a program where I am calculating large distances. I then convert the distance (a double) using stringfromnumber to get the commas inserted (i.e. 1,234,567). This works

Answer 1

You can check you're own float.h for DBL_MAX to find out. I got a value of 1.797693e+308 from:

#include <stdio.h>
#include <float.h>

int main ( void ) {
    printf("Max double %e \n", DBL_MAX);
    return 0;
}

Answer 2

A double can hold anything from infinity to negative infinity. However It can only hold 15 digits accurately. Also, keep in mind that if you cast it to an int and the double stores something larger than 2,147,483,648, the int will overflow to a negative number.