I want to extract a subarray of Columns from a multidimensional array and mutate the original array to remove those columns in JavaScript
Ex: If I have an array
originalArray =
[
[A, B, C, D, E, F],
[a1,b1,c1,d1,e1,f1],
[a2,b2,c2,d2,e2,f2],
[a3,b3,c3,d3,e3,f3]
[
Where A,B,C,D,E,F are headers
and I want to extract columns [4,0,3] in this order I would get
subArray =
[
[E, A, D],
[e1,a1,d1],
[e2,a2,d2],
[e3,a3,d3]
[
originalArray =
[
[B, C, F],
[b1,c1,f1],
[b2,c2,f2],
[b3,c3,f3]
[
I found this: Extract subarray from a multidimensional array and mutate the original array
which does this for rows
let subArray = originalArray.reduce((accumulator, current, index) => {
if (idxList.includes(index)) {
//if the current index is included in the idxList array,
//push the current value to the accumulator
accumulator.push(current);
} else {
//push the current value to the `tempArray`.
tempArray.push(current)
}
return accumulator;
}, []);
Then I will concatenate these two arrays
reorderedArray = [...subArray, ...originalArray]
Reduce seems like an interesting approach and it seems like it should be a simple fix but I have to admit I am having a hard time understanding Reduce
Thanks in advance for your assistance
You could add the missing indices to order and map the array by mapping nested array with the indices of order.
let
data = [['A', 'B', 'C', 'D', 'E', 'F'], ['a1', 'b1', 'c1', 'd1', 'e1', 'f1'], ['a2', 'b2', 'c2', 'd2', 'e2', 'f2'], ['a3', 'b3', 'c3', 'd3', 'e3', 'f3']],
order = [4, 0, 3],
seen = new Set(order),
i = 0;
while (order.length < data[0].length) {
while (seen.has(i)) ++i;
order.push(i++);
}
data = data.map(a => order.map(i => a[i]));
data.forEach(a => console.log(...a));regular mapping seems like it would work:
function myFunction() {
var originalArray = SpreadsheetApp.getActive().getRange('Sheet1!A:F').getValues();
var subarray = originalArray.map(e=>[e[4],e[0],e[3]]);
originalArray = originalArray.map(e=>[e[1],e[2],e[5]]);
}