Function to rotate matrices

rotateMatrix.js

function rotateMatrix(matrix, numRot) {
  var result = [],
      buf    = [];

  if (numRot != 0) {
    for (var i=0; i<matrix.length; i++) {
      for (var j=0; j<matrix.length; j++) {
        buf.push(matrix[j][i])
      }
      result.push(buf.reverse())
      buf = []
    }
    return rotateMatrix(result, numRot-1);
  } else {
    return matrix;
  }
}



// TEST CASES
// ------------------------------------
// Utility function to inspect a matrix
function printMatrix(matrix) {
  var line = "";
  for (var i = 0; i < matrix.length; i++) {
    for (var j = 0; j < matrix[i].length; j++) {
      if (typeof matrix[i][j] !== 'undefined') {
        line += matrix[i][j];
        line += " ";
      }
    }
    console.log(line);
    line = "";
  }
}
var matrix = [
  [1, 2, 3],
  [4, 5, 6],
  [7, 8, 9],
  [10,11,12],
]
matrix = rotateMatrix(matrix, 2)
printMatrix(matrix)

// expected 1:
//
// [10,7,4,1]
// [11,8,5,2]
// [12,9,6,3]


// expected 2:
//
// 12 11 10
// 9 8 7
// 6 5 4
// 3 2 1