/// <summary>
/// Clone an IntArray containing only the items indexed by <paramref name="itemIndices"/>
/// </summary>
/// <param name="itemIndices"> item indices will be contained in the cloned IntArray </param>
/// <returns> The cloned IntArray </returns>
public override IntArray Clone(int[] itemIndices)
{
IIntArrayForwardIndexer indexer = GetIndexer();
return(IntArray.New(itemIndices.Length, IntArrayType.Sparse, BitsPerItem, itemIndices.Select(x => indexer[x])));
}