find

find(X, Y)

X can be a vector, dictionary, in-memory table with one column, keyed table, or indexed table.

Y can be a scalar, vector, matrix, tuple, dictionary, or table.

• If X is a vector: for each element of Y, return the position of its first occurrence in vector X. If the element doesn't appear in X, return -1. (To find the positions of all occurences, please use function at.)
• If X is a dictionary: for each element of Y, if it is a key in X, return the corresponding value in X; if it is not a key in X, return NULL.
• If X is an in-memory table with one column: for each element of Y, return the position of its first occurrence in the column of X. If the element doesn't appear in X, return -1. Note the column cannot be of array vector form.
• If X is a keyed table or indexed table: for each element of Y, return the position of its first occurrence in the key columns of X. If the element doesn't appear in the key columns of X, return -1.

To search for a small amount of data in a sorted vector, we recommend to use function binsrch.

When X is a vector:

find(7 3 3 5, 3);
// output
1

at(7 3 3 5 == 3);
// output
[1,2]

(7 3 3 5 6).find(2 4 5);
// output
[-1,-1,3]

When X is a dictionary:

z=dict(1 2 3,4.5 6.6 3.2);
z;
// output
3->3.2
1->4.5
2->6.6

find(z,3);
// output
3.2
find(z,5);
// output
00F

When X is an in-memory table with one column:

t = table(1 3 5 7 9 as id)
find(t, 2 3)
// output
[-1,1]

When X is a keyed table or an indexed table:

kt = keyedTable(`name`id,1000:0,`name`id`age`department,[STRING,INT,INT,STRING])
insert into kt values(`Tom`Sam`Cindy`Emma`Nick, 1 2 3 4 5, 30 35 32 25 30, `IT`Finance`HR`HR`IT)
find(kt,(`Emma`Sam, 4 1));
// output
[3,-1]

t1 = indexedTable(`sym`side, 10000:0, `sym`side`price`qty, [SYMBOL,CHAR,DOUBLE,INT])
insert into t1 values(`IBM`MSFT`GOOG, ['B','S','B'], 10.01 10.02 10.03, 10 10 20)
find(t1, (`GOOG`MSFT, ['B','S']))
// output
[2,1]