code: public static UpdateSketch heapify(final Memory srcMem, final long seed) {
      final Family family = Family.idToFamily(srcMem.getByte(FAMILY_BYTE));
      if (family.equals(Family.ALPHA)) {
        return HeapAlphaSketch.heapifyInstance(srcMem, seed);
      }
      return HeapQuickSelectSketch.heapifyInstance(srcMem, seed);
    }
docs: Instantiates an on-heap UpdateSketch from Memory.
  @param srcMem <a href="{@docRoot}/resources/dictionary.html#mem">See Memory</a>
  @param seed <a href="{@docRoot}/resources/dictionary.html#seed">See Update Hash Seed</a>.
  @return an UpdateSketch