Question

我目前已经旋转了90度，但我不知道如何输入任何旋转数。
例如：
1.格= n * n
2. K =转数

我只能使其旋转一次，现在必须这样做，以便K可以是一个动态数。

这是我的代码！

function rotate() {
  var matrix = [[0,16,255,1],[8,128,32,1],[0,0,0,1],[1,1,1,1]];
  const N = matrix.length - 1;   // use a constant
  // use arrow functions and nested map;
  const result = matrix.map((row, i) => 
       row.map((val, j) => matrix[N - j][i])
  );
  matrix.length = 0;       // hold original array reference
  matrix.push(...result);  // Spread operator
  console.log(matrix);
  return matrix;
}

Answer 1

我的建议...

#include <iostream> 
#include <fstream> 
#include <sstream> 
using namespace std;

/* Function to sort an array using insertion sort*/
void insertionSort(int arr[], int n)
{
    int i, key, j;
    for (i = 1; i < n; i++){
        key = arr[i];
        j = i - 1;
        /* Move elements of arr[0..i-1], that aregreater than key, to one position 
 aheadof their current position */
        while (j >= 0 && arr[j] > key){
            arr[j + 1] = arr[j];
            j = j - 1;
        }
        arr[j + 1] = key;
    }
}

int arr[2000][2000];
int arr1[2000][2000];
int main()
{

    int window[9], row = 0, col = 0, numrows = 0, numcols = 0, MAX = 0;
    ifstream infile("phone.pmg");
    stringstream ss;
    string inputLine = "";

    // First line : version
    getline(infile, inputLine);
    if (inputLine.compare("P2") != 0) cerr << "Version error" << endl;
    else cout << "Version : " << inputLine << endl;

    // Continue with a stringstream
    ss << infile.rdbuf();

    // Secondline : size of image
    ss >> numcols >> numrows >> MAX;

    //print total number of rows, columns and maximum intensity of image
    cout << numcols << " columns and " << numrows << " rows" << endl<< "Maximium 
    Intesity "<< MAX <<endl; 

    //Initialize a new array of same size of image with 0
    for (row = 0; row <= numrows; ++row)
    {
        arr1[row][0] = 0;
    }
    for (col = 0; col <= numcols; ++col) {
        arr1[0][col] = 0;
    }

    // Following lines : data
    for (row = 1; row <= numrows; ++row)
    {
        for (col = 1; col <= numcols; ++col)
        {
            //original data store in new array
            ss >> arr1[row][col];
        }
    }

    // Now print the array to see the result
    for (row = 1; row <= numrows; ++row)
    {
        for (col = 1; col <= numcols; ++col)
        {
            //neighbor pixel values are stored in window including this pixel
            window[0] = arr1[row - 1][col - 1];
            window[1] = arr1[row - 1][col];
            window[2] = arr1[row - 1][col + 1];
            window[3] = arr1[row][col - 1];
            window[4] = arr1[row][col];
            window[5] = arr1[row][col + 1];
            window[6] = arr1[row + 1][col - 1];
            window[7] = arr1[row + 1][col];
            window[8] = arr1[row + 1][col + 1];

            //sort window array
            insertionSort(window, 9);

            //put the median to the new array 
            arr[row][col] = window[4];
        }
    }

    ofstream outfile;

    //new file open to stroe the output image 
    outfile.open("Medianfilter.pmn ");
    outfile << "P2" << endl;
    outfile << numcols << " " << numrows << endl;
    outfile << "255" << endl;

    for (row = 1; row <= numrows; ++row)
    {
        for (col = 1; col <= numcols; ++col)
        {
            //store resultant pixel values to the output file
            outfile << arr[row][col] << " ";
        }
    }

    outfile.close();
    infile.close();
    return 0;
}

Array.prototype.Rotate = function(RotateNumber)
  {
  let len = this.length

  for (let l of this)
    {
    if ( !Array.isArray(l))  throw "this is not a matrix !"
    if (l.length!==len)      throw "this is not a square matrix !"
    }

  let r = RotateNumber %4   // max 3 rotates
  if (r<0) r +=4           // for negative rotates

  for(n=r;n--;)
    {
    let temp = this.map((r,i,A)=>
                { 
                let t=[]
                for(let j=A.length;j--;) t.push(A[j][i])
                return t 
                })
    this.forEach((r,i)=>r.forEach((c,j)=>this[i][j]=temp[i][j])) // copy values
    }
  return this
  }


///////////////////////////////////// test part ///////////////////
function matrixDisplay(comment,matrix)
  {
  let prev = '[ ' 
  console.log(comment, ' =')

  for(let line of matrix)
    {
    console.log ( prev + '[ ' + line.map(col=>`'${col}'`).join(', ') + ' ]' )
    prev = ', '
    }
  console.log(']')
  }
  
  var matrix = 
      [ [ 'a', 'b', 'c', 'd' ] 
      , [ '1', '2', '3', '4' ] 
      , [ 'X', 'Y', 'Z', 'W' ] 
      , [ '8', '7', '6', '5' ] 
      ] 


matrixDisplay('matrix start', matrix ,3)
matrixDisplay('matrix R2',    matrix.Rotate(2),3)
matrixDisplay('matrix R-3',   matrix.Rotate(-3),3)
matrixDisplay('matrix R1',    matrix.Rotate(1),3)

如何将数组矩阵n x n旋转k次？

1 个答案: