code: static DirectQuickSelectSketchR readOnlyWrap(final Memory srcMem, final long seed) {
      final int preambleLongs = extractPreLongs(srcMem);                  //byte 0
      final int lgNomLongs = extractLgNomLongs(srcMem);                   //byte 3
      final int lgArrLongs = extractLgArrLongs(srcMem);                   //byte 4
  
      UpdateSketch.checkUnionQuickSelectFamily(srcMem, preambleLongs, lgNomLongs);
      checkMemIntegrity(srcMem, seed, preambleLongs, lgNomLongs, lgArrLongs);
  
      final DirectQuickSelectSketchR dqssr =
          new DirectQuickSelectSketchR(seed, (WritableMemory) srcMem);
      dqssr.hashTableThreshold_ = setHashTableThreshold(lgNomLongs, lgArrLongs);
      return dqssr;
    }
docs: Wrap a sketch around the given source Memory containing sketch data that originated from
  this sketch.
  @param srcMem <a href="{@docRoot}/resources/dictionary.html#mem">See Memory</a>
  The given Memory object must be in hash table form and not read only.
  @param seed <a href="{@docRoot}/resources/dictionary.html#seed">See Update Hash Seed</a>
  @return instance of this sketch