I'm not quite sure why I can't do 

```
double a = (double) my_Function(45) / 2048 / 2340 / 90;
printf("%.4f",a); // prints out 0.00

```

But instead I have to use one more variable as:

```
double a = (double) my_Function(45);
double b = a  / 2048 / 2340 / 90;
printf("%.4f",b);  // prints out the correct value

```