Package org.apache.druid.hll
package org.apache.druid.hll
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ClassesClassDescriptionImplements the HyperLogLog cardinality estimator described in: http://algo.inria.fr/flajolet/Publications/FlFuGaMe07.pdf Run this code to see a simple indication of expected errors based on different m values:
for (int i = 1; i < 20; ++i) { System.out.printf("i[%,d], val[%,d] => error[%f%%]%n", i, 2 << i, 104 / Math.sqrt(2 << i)); }This class is *not* multi-threaded.Contains data hashing methods used before applying Hyper Log Log.Deprecated.