You can use the modulus operator.
For example 5 % 1 will return 0
However, 5.1 % 1 will return 0.1
so you could use
so if somevalue % 1 == 0 .... then you know that somevalue is an integer otherwise it is fp
for testing type in 5%1 in google search to calculate the result. Then type in 5.1%1 in a google search to see that result. Try different combinations of numbers and you will understand what is going on.
hope this helps