Saving/Storing a multidimensional array

[GoToLoop]

@Baz

Do you think JSON can be used, or is there other methods that could work?

• 1st of all, you’re gonna need a function which converts your multidimensional array to a JSONArray container.
• Inside a multi-loop, use method append() to add more JSONArray containers, and finally the values themselves inside the innermost dimension:
  append() / Reference / Processing.org
• Then you can use saveJSONArray() to save it as a JSON file:
  saveJSONArray() / Reference / Processing.org

/**
 * Conversion Arr3d to JSONArr3d (v0.1)
 * GoToLoop (2019/Dec/14)
 * Discourse.Processing.org/t/saving-storing-a-multidimensional-array/16391/3
 */

static final String FILENAME = "JArr3D.json", OPT = "compact";

double[][][] my3dArr = new double[4][2][3];
JSONArray myJArr;

void setup() {
  myJArr = arr3dToJArr(my3dArr);
  println(myJArr);
  saveJSONArray(myJArr, dataPath(FILENAME), OPT);
  exit();
}

static final JSONArray arr3dToJArr(final double[][][] arr3d) {
  final JSONArray jarr3d = new JSONArray();

  for (final double[][] arr2d : arr3d) {
    final JSONArray jarr2d = new JSONArray();
    jarr3d.append(jarr2d);

    for (final double[] arr1d : arr2d) {
      final JSONArray jarr1d = new JSONArray();
      jarr2d.append(jarr1d);

      for (final double d : arr1d)  jarr1d.append(d);
    }
  }

  return jarr3d;
}

I did the Arr3d to JArray part. You just need to do the reverse.