public byte get(long index) {
    return array[segment(index)][offset(index)];
  }
Returns the element of this big array at specified index.

@param index a position in this big array.
@return the element of this big array at the specified position.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/source/relational/aggregation/grouped/array/ByteBigArray.java