Purpose
Returns one less than the length,
in bits, of the twos complement representation of an integer.
Argument type and attributes
- I
- An INTENT(IN) INTEGER
Result type and attributes
Same as I.
Result value
- If I is negative, ILEN(I)=CEILING(LOG2(-I))
- If I is nonnegative, ILEN(I)=CEILING(LOG2(I+1))
Examples
I=ILEN(4) ! 3
J=ILEN(-4) ! 2