eachLeft (:L)
Syntax
eachLeft(func, X, Y, [consistent=false])
or
X <operator>:L Y (when consistent = false)
or
X <operator>:LC Y (when consistent = true)
or
func:L(X, Y, [consistent=false])
Arguments
func is a binary function.
X/ Y is a vector/matrix/table/dictionary.
consistent is a Boolean value. The default value is false, indicating that the data type of the result is determined by each calculation result. Otherwise, the data type of the result is the same as the data type of the first calculation result. Note that if the data forms of result are inconsistent, consistent can only be specified as false. Otherwise, an error will be reported.
Details
Calculate func(X(i),Y) for each element of X.
X(i) is each element when X is a vector.
X(i) is each column when X is a matrix.
X(i) is each row when X is a table.
X(i) is each value when X is a dictionary.
If func supports vector operation and the input is a vector, we should use the vector function/operator directly instead of the eachLeft template for better performance.
Examples
eachLeft with 2 vectors:
$ x = 4 3 2 1
$ y = 3 0 6;
$ x +:L y;
4 |
3 |
2 |
1 |
|---|---|---|---|
7 |
6 |
5 |
4 |
4 |
3 |
2 |
1 |
10 |
9 |
8 |
7 |
$ eachLeft(pow, x, y);
4 |
3 |
2 |
1 |
|---|---|---|---|
64 |
27 |
8 |
1 |
1 |
1 |
1 |
1 |
4096 |
729 |
64 |
1 |
eachLeft with a vector and a matrix:
$ x=1..6$2:3;
$ x;
col1 |
col2 |
col3 |
|---|---|---|
1 |
3 |
5 |
2 |
4 |
6 |
$ x ** :L 1 1;
[3,7,11]
eachLeft with 2 matrices:
$ y=6..1$2:3;
$ y;
col1 |
col2 |
col3 |
|---|---|---|
6 |
4 |
2 |
5 |
3 |
1 |
$ z = x **:L y;
$ z;
(#0 #1 #2
-- -- --
16 10 4
,#0 #1 #2
-- -- --
38 24 10
,#0 #1 #2
-- -- --
60 38 16
)
$ typestr z;
ANY VECTOR
eachLeft with a dictionary and a vector:
$ d=dict(`a`b`c, [[1, 2, 3],[4, 5, 6], [7, 8, 9]])
$ eachLeft(add,d,10 20 30)
a->[11,22,33]
b->[14,25,36]
c->[17,28,39]