来自 arrays 数组的块数据

Question

Before marking this as answered by another question please note this is an array of arrays, not a flat array, also, the number I have given are an example, I have just shown them so you can visually see what is happening.

I am trying to loop through an array of arrays. I have the following array:-

[
   [1, 2, 3, 4, 5, 6, 7, 8, 9],
   [1, 2, 3, 4, 5, 6, 7, 8, 9],
   [1, 2, 3, 4, 5, 6, 7, 8, 9],
   [3, 2, 1, 6, 5, 4, 9, 8, 7],
   [6, 5, 4, 9, 8, 7, 3, 2, 1],
   [7, 8, 9, 3, 2, 1, 6, 5, 4]
]

How is it possible to transform this array into chunks of 3x3 for example:-

[
   [1, 2, 3, 1, 2, 3, 1, 2, 3],
   [4, 5, 6, 4, 5, 6, 4, 5, 6],
   [7, 8, 9, 7, 8, 9, 7, 8, 9],
   [3, 2, 1, 6, 5, 4, 9, 8, 7],
   [6, 5, 4, 9, 8, 7, 3, 2, 1],
   [7, 8, 9, 3, 2, 1, 6, 5, 4],
]

As you can see from the array above I have chunked it using the first 3 values from each array and then by the 2nd 3n from each array and lastly the final 3n from each array.

So the array would be chunked like the following:-

1 2 3 | 4 5 6 | 7 8 9
1 2 3 | 4 5 6 | 7 8 9
1 2 3 | 4 5 6 | 7 8 9
---------------------
3 2 1 | 6 5 4 | 9 8 7
6 5 4 | 9 8 7 | 3 2 1
7 8 9 | 3 2 1 | 6 5 4

I have tried to loop through each line and resetting the column count when it hits an increment and increasing the row but this didn't work.

I can update the question with previous attempts if this is of any help? Also just a note, the array will be different sizes but always divisible by a particular number, for the above example I have chosen the number 3.

I have updated the question with more information. The array of arrays will always be divisible by a specific number, this example shows a divisible number of 3.

Answer 1

 const array = [ [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9], ]; function chunk(array, chunk) { let result = []; for (let i = 0; i < array.length; i += chunk) { result.push(array.slice(i, i + chunk)); } return result; } const zip = (...rows) => [...rows[0]].map((_, c) => rows.map((row) => row[c])); const chunked = zip(...array.map((arr) => chunk(arr, 3))).map((arr) => arr.flat() ); console.log(chunked);

Answer 2

You can do it with a nested loop, slicing the array each time based on the size of the outer array.

 const arr = [ [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9] ]; let out = []; for(let i in arr) { out.push([]);} arr.forEach((e, i) => { let scale = e.length / arr.length; for(let j in arr) { out[j] = out[j].concat(e.slice(j * scale, j * scale + scale)); } }); console.log(out);

Here it is once more with your original array prior to your edit:

 const arr = [ [1, 3, 2, 5, 2, 4, 3, 6, 8], [1, 4, 3, 6, 7, 3, 6, 4, 5], [2, 4, 1, 4, 6, 3, 7, 9, 7] ]; let out = []; for(let i in arr) { out.push([]);} arr.forEach((e, i) => { let scale = e.length / arr.length; for(let j in arr) { out[j] = out[j].concat(e.slice(j * scale, j * scale + scale)); } }); console.log(out);

Answer 3

Dynamic solution:

 const arr = [ [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9], ]; const columns = arr[0].length; const rows = arr.length; const result = []; for (let i = 0; i < arr.length; i++) { let count = 0; let prevElements = []; for (let j = 0; j < arr[i].length; j++) { prevElements.push(arr[i][j]); if ((j + 1) % (columns / rows) === 0) { result[count] = result[count] || []; result[count] = [...result[count], ...prevElements]; prevElements = []; count++; } } } console.log(result);