How to check if a double value has no decimal part [duplicate]

Answer 1

You probably want to round the double to 5 decimals or so before comparing since a double can contain very small decimal parts if you have done some calculations with it.

double d = 10.0;
d /= 3.0; // d should be something like 3.3333333333333333333333...
d *= 3.0; // d is probably something like 9.9999999999999999999999...

// d should be 10.0 again but it is not, so you have to use rounding before comparing

d = myRound(d, 5); // d is something like 10.00000
if (fmod(d, 1.0) == 0)
  // No decimals
else
  // Decimals

If you are using C++ i don't think there is a round-function, so you have to implement it yourself like in: http://www.cplusplus.com/forum/general/4011/

Answer 2

double d = 14.4;
if((d-(int)d)!=0)
    System.out.println("decimal value is there");
else
    System.out.println("decimal value is not there");