signum

signum(X)

Alias: sign

Return 1 if X is positive; 0 if X is 0; -1 if X is negative; NULL if X is null.

x is a scalar/vector/matrix of numeric or Boolean value.

Returns 1 if X is positive, 0 if X is 0, -1 if X is negative, and NULL if an element of X is NULL.

signum 1 0 -1 NULL;
// output: [1,0,-1, ]