supports Boolean operations & and & $($logical AND$),$ and $($logical OR$),!$ NOT $($logical negation$)$ and, $($function for XOR, exclusive OR$).$ The shorter forms $($& and $(1)$ perform comparisons element by element as the arithmetic operations do$.$ The longer forms $($&& and $($II$)$ ev$$luate left to right looking only at the first element of each vector; evaluation proceeds only until the result is determined.

If a and $b$ are two logical vectors the

length $(x$& &