NdArray implementations don't throw IllegalRankException as documented if no coordinates provided

Instead, when no coordinates are provided, we return the scalar at (0, 0, ...). Is this an important idiom that we are preserving, or a questionable choice, or simply a bug?

Here's an example of an abstract method of FloatNdArray that is documented to throw IllegalRankException:

 /**
   * Returns the float value of the scalar found at the given coordinates.
   *
   * . . .
   *
   * @param coordinates coordinates of the scalar to resolve
   * @return value of that scalar
   * @throws IndexOutOfBoundsException if some coordinates are outside the limits of their respective dimension
   * @throws IllegalRankException if number of coordinates is not sufficient to access a scalar element
   */
  float getFloat(long... coordinates);

Here's the implementation in FloatDenseNdArray:

  @Override
  public float getFloat(long... indices) {
    return buffer.getFloat(positionOf(indices, true));
  }

But if indices.length == 0, then positionOf does not throw the claimed IllegalRankException:

  long positionOf(long[] coords, boolean isValue) {
    if (coords == null || coords.length == 0) {
      return 0;
    }
    Validator.coordinates(dimensions, coords, isValue);
    return dimensions.positionOf(coords);
  }

Commencez par le contrat documenté de FloatNdArray.getFloat et comparez-le à FloatDenseNdArray.getFloat et positionOf, en particulier la branche des coordonnées nulles. Déterminez si le fait de renvoyer le scalaire à la position 0 est intentionnel ou enfreint le comportement documenté des exceptions ; le travail est terminé lorsque le comportement et sa documentation concordent, avec la couverture pertinente ajoutée ou mise à jour si le projet en fournit.