code: public static double getEstimate(final Memory srcMem) {
      checkIfValidThetaSketch(srcMem);
      return Sketch.estimate(getThetaLong(srcMem), getRetainedEntries(srcMem), getEmpty(srcMem));
    }
docs: Gets the unique count estimate from a valid memory image of a Sketch
  @param srcMem <a href="{@docRoot}/resources/dictionary.html#mem">See Memory</a>
  @return the sketch's best estimate of the cardinality of the input stream.