My goal is to rotate the image represented by matrix (a) by mapping the values in the "a" coordinates to the rotated image, as shown below. However, I am puzzled as to why this method fails to produce the desired result.
a = [[1, 2, 3],
[4, 5, 6],
[7, 8, 9]]
// Desired output:
// rotateImage(a) =
// [[7, 4, 1],
// [8, 5, 2],
// [9, 6, 3]]
// aCoords = [[00,01,02],
// [10, 11, 12],
// [20,21,22]]
// rotatedImageCoordsRelatingToa = [[20, 10, 00],
// [21, 11, 01],
// [22,12,02]]
function rotateImage(a) {
const image = [...a]
const length = a.length
const rotatedImage = [...a]
for(let i=0;i<length;i++){
for(let j=0;j<length;j++){
let toRotateCoord = length-(1+j)
console.log("Original coordinates:" + i,j + " should map to rotated coordinates:"+ toRotateCoord, i)
rotatedImage[i][j] = image[toRotateCoord][i]
}
}
return rotatedImage;
}
rotateImage(a);
Upon execution, the actual outcome differs from the expected rotation:
//[[7,4,7],
// [8,5,4],
// [9,4,7]]
// Instead of
// [[7, 4, 1],
// [8, 5, 2],
// [9, 6, 3]]
While I understand that there may be more efficient algorithms for achieving this rotation, I am intrigued by the reasons behind the failure of this approach. It appears that the issue lies in the way the arrays are accessed.