Comparing currency values as floats does not work

Question

If I type 0.01 or 0.02 the the program just exits immediately. What do I do?

#include 

char line[100];
float amount;

int main()
{
printf(\"E         


        

Answer 1

I think we could scale for a factor and make a relative comparison like this:

#define EPSILON (0.000001)

if (fabs(a - b) <= EPSILON * fmax(fabs(a), fabs(b))) {
}

which is more robust than an absolute comparison:

if (fabs(a - b) <= EPSILON ) {
    // ...
}

which maybe scale dependent. By the way having the optimum scale depends also from the function, we shouldn't use the same formula for a log and for a sin.