bitnot()  the bitwise arithmetic not

 x=bitnot(a)

This function is used to compute the bitwise not of its single argument. The argument is treated as binary number (i.e. a sequence of digits 0 and 1); a bit of the resulting value will be 1, if the argument has a 0 at this position in its binary representation; if the bit in the argument is 1, the bit in the result will be 0.

Note, that its argument is silently converted to a positive integer value and that negative numbers have their own binary representation and may lead to unexpected results when passed to bitnot.

A note on naming: This one-argument-function is named bitnot to distinguish it from the one-argument-function not, which operates on logical expressions. For the similar functions and and or this distinction between logical and bitwise function is done implicitly through the number of arguments (1 and 2, respectively).

print bin$(bitnot(17))

          
This will print 11111111111111111111111111101110. This result is clear, if you note, that the binary representation of 17 is 10001, which inverted will give the long binary number given before.