Floating point numbers ...

Floating point numbers have some unexpected properties.

Try this in your favourite language (if it has real floats)

Python:

>>> print 0.1 + 0.2 == 0.3

False

 C:

#include <stdio.h>

int main() {  printf("%s\n", 0.1 + 0.2 == 0.3 ? "True" : "False");

} 

$ gcc float.c -o float && ./float 

False