code: public static double[] toDouble(int[] array) {
          double[] n = new double[array.length];
          for (int i = 0; i < array.length; i++) {
              n[i] = (double) array[i];
          }
          return n;
      }
docs: 1-D Integer array to double array.
  
  @param array Integer array.
  @return Double array.