Purpose
Population count
Counts the number of set bits in a data object.
Class
Elemental function
Argument type and attributes
- I
- An INTENT(IN) argument of type integer
The argument can also be of type byte, logical,
or real. If the type of the argument is real, it must not be REAL(16).
Result type and attributes
Default integer
Result value
The number of bits set to 1 in the sequence of bits of I
Examples
The following table
shows the functionality of the POPCNT function.
| Integer | Bit Representation | POPCNT |
| 0 | 0000 | 0 |
| 1 | 0001 | 1 |
| 2 | 0010 | 1 |
| 3 | 0011 | 2 |
| 4 | 0100 | 1 |