firstNot

Syntax

firstNot(X, [k])

Arguments

X can be a scalar, pair, vector, matrix or table.

k (optional) is a scalar.

Details

If X is a vector:

  • If k is not specified: return the first element of X that is not NULL.

  • If k is specified: return the first element of X that is neither k nor NULL.

If X is a matrix or table, conduct the aforementioned calculation within each column of X. The result is a vector.

Examples

firstNot(0 0 0 6 1, 0);
// output
6

firstNot(NULL 0 3 2 1, 0);
// output
3

firstNot(NULL 0 1 6);
// output
0

t=table(1 1 1 1 1 2 2 2 2 2 as id, 0 0 0 2 1 NULL NULL 0 0 3 as x);
t;
id x
1 0
1 0
1 0
1 2
1 1
2
2
2 0
2 0
2 3 
select firstNot(x, 0) from t group by id;
id firstNot_x
1 2
2 3 
m=matrix(0 NULL 1 2 3, NULL 2 NULL 0 3);
m;
#0 #1
0 2
1
2 0
3 3 
firstNot(m, 0);
// output
[1,2]