not

not(X) or !(X)

X is a scalar/pair/vector/matrix.

Return NOT of each element of X. Returned values are 0, 1, or NULL. NOT of 0 is 1; NOT of NULL is still NULL; NOT of all other values is 0.

Though not and the ! operator often serve analogous purposes, precedence behavior differs:

• The not function, when parenthesized carries the highest priority. Without parentheses, not has lower precedence than the following expression, e.g., not false and false is equivalent to not(false and false), which returns true.

• The ! operator always follows the precedence rule. For example: ！false and false is equivalent to (!false) and false, which returns false.

!1.5;
// output
0

not 0;
// output
1

x=1 0 2;
not x;
// output
[0,1,0]

m=1 1 1 1 1 0 0 0 0 0$2:5;
m;

not m;

(1).not();
// output
0

(!NULL)==NULL;
// output
1

Related functions: and, or