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<h4>API Snapshots:
<a href="https://apache.github.io/datasketches-java/4.2.0/">Java Core</a>,
<a href="https://apache.github.io/datasketches-cpp/5.0.0/">C++ Core</a>,
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<p id="background">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_background">Background</a>
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<li><a href="/docs/Background/TheChallenge.html">•The Challenge</a></li>
<li><a href="/docs/Background/SketchOrigins.html">•Sketch Origins</a></li>
<li><a href="/docs/Background/SketchElements.html">•Sketch Elements</a></li>
<li><a href="/docs/Background/Presentations.html">•Presentations</a></li>
<li><a href="https://github.com/apache/datasketches-website/tree/master/docs/pdf/DataSketches_deck.pdf">•Overview Slide Deck</a></li>
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<p id="architecture-and-design">
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<li><a href="/docs/Architecture/MajorSketchFamilies.html">•The Major Sketch Families</a></li>
<li><a href="/docs/Architecture/LargeScale.html">•Large Scale Computing</a></li>
<li><a href="/docs/Architecture/KeyFeatures.html">•Key Features</a></li>
<li><a href="/docs/Architecture/SketchFeaturesMatrix.html">•Sketch Features Matrix</a></li>
<li><a href="/docs/Architecture/Components.html">•Components</a></li>
<li><a href="/docs/Architecture/SketchesByComponent.html">•Sketches by Component</a></li>
<li><a href="/docs/Architecture/SketchCriteria.html">•Sketch Criteria</a></li>
<p id="memory-component">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_memory_component">Memory Component</a>
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<li><a href="/docs/Memory/MemoryComponent.html">•Memory Component</a></li>
<li><a href="/docs/Memory/MemoryPerformance.html">•Memory Component Performance</a></li>
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<li><a href="/docs/Architecture/OrderSensitivity.html">•Notes on Order Sensitivity</a></li>
<li><a href="/docs/Architecture/Concurrency.html">•Notes on Concurrency</a></li>
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<p id="sketch-families">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_sketch_families">Sketch Families</a>
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<p id="distinct-counting">
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<li><a href="/docs/DistinctCountFeaturesMatrix.html">•Features Matrix</a></li>
<li><a href="/docs/DistinctCountMeritComparisons.html">•Figures-of-Merit Comparison</a></li>
<p id="cpc-sketches">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_cpc_sketches">CPC Sketches</a>
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<li><a href="/docs/CPC/CPC.html">•CPC Sketch</a></li>
<li><a href="/docs/CPC/CpcPerformance.html">•CPC Sketch Performance</a></li>
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<li><a href="/docs/CPC/CpcJavaExample.html">•CPC Sketch Java Example</a></li>
<li><a href="/docs/CPC/CpcCppExample.html">•CPC Sketch C++ Example</a></li>
<li><a href="/docs/CPC/CpcPigExample.html">•CPC Sketch Pig UDFs</a></li>
<li><a href="/docs/CPC/CpcHiveExample.html">•CPC Sketch Hive UDFs</a></li>
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<p id="hyperloglog-sketches">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_hyperloglog_sketches">HyperLogLog Sketches</a>
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<li><a href="/docs/HLL/HLL.html">•HLL Sketch</a></li>
<li><a href="/docs/HLL/HllMap.html">•HLL Map Sketch</a></li>
<p id="hll-examples">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_hll_examples">HLL Examples</a>
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<li><a href="/docs/HLL/HllJavaExample.html">•HLL Sketch Java Example</a></li>
<li><a href="/docs/HLL/HllCppExample.html">•HLL Sketch C++ Example</a></li>
<li><a href="/docs/HLL/HllPigUDFs.html">•HLL Sketch Pig UDFs</a></li>
<li><a href="/docs/HLL/HllHiveUDFs.html">•HLL Sketch Hive UDFs</a></li>
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<li><a href="/docs/HLL/HllPerformance.html">•HLL Sketch Performance</a></li>
<li><a href="/docs/HLL/Hll_vs_CS_Hllpp.html">•HLL vs Clearspring HLL++</a></li>
<li><a href="/docs/HLL/HllSketchVsDruidHyperLogLogCollector.html">•HLL Sketch vs Druid HyperLogLogCollector</a></li>
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<p id="theta-sketches">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_theta_sketches">Theta Sketches</a>
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<li><a href="/docs/Theta/ThetaSketchFramework.html">•Theta Sketch Framework</a></li>
<p id="theta-examples">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_theta_examples">Theta Examples</a>
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<li><a href="/docs/Theta/ConcurrentThetaSketch.html">•Concurrent Theta Sketch</a></li>
<li><a href="/docs/Theta/ThetaJavaExample.html">•Theta Sketch Java Example</a></li>
<li><a href="/docs/Theta/ThetaSparkExample.html">•Theta Sketch Spark Example</a></li>
<li><a href="/docs/Theta/ThetaPigUDFs.html">•Theta Sketch Pig UDFs</a></li>
<li><a href="/docs/Theta/ThetaHiveUDFs.html">•Theta Sketch Hive UDFs</a></li>
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<p id="kmv-tutorial">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_kmv_tutorial">KMV Tutorial</a>
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<li><a href="/docs/Theta/InverseEstimate.html">•The Inverse Estimate</a></li>
<li><a href="/docs/Theta/KMVempty.html">•Empty Sketch</a></li>
<li><a href="/docs/Theta/KMVfirstEst.html">•First Estimator</a></li>
<li><a href="/docs/Theta/KMVbetterEst.html">•Better Estimator</a></li>
<li><a href="/docs/Theta/KMVrejection.html">•Rejection Rules</a></li>
<li><a href="/docs/Theta/KMVupdateVkth.html">•Update V(kth) Rule</a></li>
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<p id="set-operations-and-p-sampling">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_set_operations_and_p-sampling">Set Operations and P-sampling</a>
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<li><a href="/docs/Theta/ThetaSketchSetOps.html">•Set Operations</a></li>
<li><a href="/docs/Theta/ThetaSetOpsCornerCases.html">•Model & Test Set Operations</a></li>
<li><a href="/docs/Theta/ThetaPSampling.html"><i>p</i>-Sampling</a></li>
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<p id="accuracy">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_accuracy">Accuracy</a>
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<li><a href="/docs/Theta/ThetaAccuracy.html">•Basic Accuracy</a></li>
<li><a href="/docs/Theta/ThetaAccuracyPlots.html">•Accuracy Plots</a></li>
<li><a href="/docs/Theta/ThetaErrorTable.html">•Relative Error Table</a></li>
<li><a href="/docs/Theta/ThetaSketchSetOpsAccuracy.html">•SetOp Accuracy</a></li>
<li><a href="/docs/Theta/AccuracyOfDifferentKUnions.html">•Unions With Different k</a></li>
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<p id="size">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_size">Size</a>
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<div class="collapse" id="collapse_size">
<li><a href="/docs/Theta/ThetaSize.html">•Theta Sketch Size</a></li>
</div>
<p id="speed">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_speed">Speed</a>
</p>
<div class="collapse" id="collapse_speed">
<li><a href="/docs/Theta/ThetaUpdateSpeed.html">•Update Speed</a></li>
<li><a href="/docs/Theta/ThetaMergeSpeed.html">•Merge Speed</a></li>
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<p id="theta-sketch-theory">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_theta_sketch_theory">Theta Sketch Theory</a>
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<div class="collapse" id="collapse_theta_sketch_theory">
<li><a href="https://github.com/apache/datasketches-website/tree/master/docs/pdf/ThetaSketchFramework.pdf">•Theta Sketch Framework (PDF)</a></li>
<li><a href="https://github.com/apache/datasketches-website/tree/master/docs/pdf/ThetaSketchEquations.pdf">•Theta Sketch Equations (PDF)</a></li>
<li><a href="https://github.com/apache/datasketches-website/tree/master/docs/pdf/DataSketches.pdf">•DataSketches (PDF)</a></li>
<li><a href="/docs/Theta/ThetaConfidenceIntervals.html">•Confidence Intervals Notes</a></li>
<li><a href="/docs/Theta/ThetaMergingAlgorithm.html">•Merging Algorithm Notes</a></li>
<li><a href="/docs/Theta/ThetaReferences.html">•Theta References</a></li>
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<p id="tuple-sketches">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_tuple_sketches">Tuple Sketches</a>
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<li><a href="/docs/Tuple/TupleOverview.html">•Tuple Overview</a></li>
<p id="tuple-examples">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_tuple_examples">Tuple Examples</a>
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<li><a href="/docs/Tuple/TupleJavaExample.html">•Tuple Java Example</a></li>
<li><a href="/docs/Tuple/TupleEngagementExample.html">•Tuple Engagement Example</a></li>
<li><a href="/docs/Tuple/TuplePigUDFs.html">•Tuple Pig UDFs</a></li>
<li><a href="/docs/Tuple/TupleHiveUDFs.html">•Tuple Hive UDFs</a></li>
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</div>
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<p id="most-frequent">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_most_frequent">Most Frequent</a>
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<div class="collapse" id="collapse_most_frequent">
<li><a href="/docs/Frequency/FrequencySketchesOverview.html">•Frequency Sketches Overview</a></li>
<p id="frequent-item-sketches">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_frequent_item_sketches">Frequent Item Sketches</a>
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<li><a href="/docs/Frequency/FrequentItemsOverview.html">•Frequent Items Overview</a></li>
<li><a href="/docs/Frequency/FrequentItemsErrorTable.html">•Frequent Items Error Table</a></li>
<li><a href="/docs/Frequency/FrequentItemsReferences.html">•Frequent Items References</a></li>
<li><a href="/docs/Frequency/FrequentItemsPerformance.html">•Frequent Items Performance</a></li>
<p id="most-frequent-examples">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_most_frequent_examples">Most Frequent Examples</a>
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<li><a href="/docs/Frequency/FrequentItemsJavaExample.html">•Frequent Items Java Example</a></li>
<li><a href="/docs/Frequency/FrequentItemsCppExample.html">•Frequent Items C++ Example</a></li>
<li><a href="/docs/Frequency/FrequentItemsPigUDFs.html">•Frequent Items Pig UDFs</a></li>
<li><a href="/docs/Frequency/FrequentItemsHiveUDFs.html">•Frequent Items Hive UDFs</a></li>
</div>
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<p id="frequent-distinct-sketches">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_frequent_distinct_sketches">Frequent Distinct Sketches</a>
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<li><a href="/docs/Frequency/FrequentDistinctTuplesSketch.html">•Frequent Distinct Tuples Sketch</a></li>
</div>
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<p id="quantiles-and-histograms">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_quantiles_and_histograms">Quantiles And Histograms</a>
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<li><a href="/docs/Quantiles/SketchingQuantilesAndRanksTutorial.html">•Quantiles and Ranks Tutorial</a></li>
<li><a href="/docs/Quantiles/QuantilesOverview.html">•Quantiles Overview</a></li>
<li><a href="/docs/KLL/KLLSketch.html">•KLL Floats sketch</a></li>
<li><a href="/docs/KLL/KLLAccuracyAndSize.html">•KLL Sketch Accuracy and Size</a></li>
<li><a href="/docs/REQ/ReqSketch.html">•REQ Floats sketch</a></li>
<li><a href="/docs/Quantiles/OrigQuantilesSketch.html">•Original QuantilesSketch</a></li>
<p id="quantiles-examples">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_quantiles_examples">Quantiles Examples</a>
</p>
<div class="collapse" id="collapse_quantiles_examples">
<li><a href="/docs/Quantiles/QuantilesJavaExample.html">•Quantiles Sketch Java Example</a></li>
<li><a href="/docs/KLL/KLLCppExample.html">•KLL Quantiles Sketch C++ Example</a></li>
<li><a href="/docs/Quantiles/QuantilesPigUDFs.html">•Quantiles Sketch Pig UDFs</a></li>
<li><a href="/docs/Quantiles/QuantilesHiveUDFs.html">•Quantiles Sketch Hive UDFs</a></li>
</div>
<p id="quantiles-studies">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_quantiles_studies">Quantiles Studies</a>
</p>
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<li><a href="/docs/QuantilesStudies/DruidApproxHistogramStudy.html">•Druid Approximate Histogram</a></li>
<li><a href="/docs/QuantilesStudies/MomentsSketchStudy.html">•Moments Sketch Study</a></li>
<li><a href="/docs/QuantilesStudies/QuantilesStreamAStudy.html">•Quantiles StreamA Study</a></li>
<li><a href="/docs/QuantilesStudies/ExactQuantiles.html">•Exact Quantiles for Studies</a></li>
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<p id="quantiles-sketch-theory">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_quantiles_sketch_theory">Quantiles Sketch Theory</a>
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<li><a href="https://github.com/apache/datasketches-website/tree/master/docs/pdf/Quantiles_KLL.pdf">•Optimal Quantile Approximation in Streams</a></li>
<li><a href="/docs/Quantiles/QuantilesReferences.html">•Quantiles References</a></li>
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</div>
<p id="sampling">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_sampling">Sampling</a>
</p>
<div class="collapse" id="collapse_sampling">
<li><a href="/docs/Sampling/ReservoirSampling.html">•Reservoir Sampling</a></li>
<li><a href="/docs/Sampling/ReservoirSamplingPerformance.html">•Reservoir Sampling Performance</a></li>
<li><a href="/docs/Sampling/VarOptSampling.html">•VarOpt Sampling</a></li>
<p id="sampling-examples">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_sampling_examples">Sampling Examples</a>
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<div class="collapse" id="collapse_sampling_examples">
<li><a href="/docs/Sampling/ReservoirSamplingJava.html">•Reservoir Sampling Java Example</a></li>
<li><a href="/docs/Sampling/ReservoirSamplingPigUDFs.html">•Reservoir Sampling Pig UDFs</a></li>
<li><a href="/docs/Sampling/VarOptSamplingJava.html">•VarOpt Sampling Java Example</a></li>
<li><a href="/docs/Sampling/VarOptPigUDFs.html">•VarOpt Sampling Pig UDFs</a></li>
</div>
</div>
</div>
<p id="system-integrations">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_system_integrations">System Integrations</a>
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<div class="collapse" id="collapse_system_integrations">
<li><a href="/docs/SystemIntegrations/ApacheDruidIntegration.html">•Using Sketches in ApacheDruid</a></li>
<li><a href="/docs/SystemIntegrations/ApacheHiveIntegration.html">•Using Sketches in Apache Hive</a></li>
<li><a href="/docs/SystemIntegrations/ApachePigIntegration.html">•Using Sketches in Apache Pig</a></li>
<li><a href="/docs/SystemIntegrations/PostgreSQLIntegration.html">•Using Sketches in PostgreSQL</a></li>
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<a data-toggle="collapse" class="menu collapsed" href="#collapse_community">Community</a>
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<li><a href="/docs/Community/index.html">•Community</a></li>
<li><a href="/docs/Community/Downloads.html">•Downloads</a></li>
<li><a href="/docs/Community/NewCommitterProcess.html">•Committer Process</a></li>
<li><a href="/docs/Community/ReleaseProcessForCppComponents.html">•Release Process For CPP Components</a></li>
<li><a href="/docs/Community/ReleaseProcessForJavaComponents.html">•Release Process For Java Components</a></li>
<li><a href="/docs/Community/Transitioning.html">•Transitioning from prior GitHub Site</a></li>
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<p id="research">
<a data-toggle="collapse" class="menu collapsed" href="#collapse_research">Research</a>
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<li><a href="/docs/Community/Research.html">•Research</a></li>
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<h1 id="running-characterization-remotely">Running Characterization Remotely</h1>
<p>The following is a short manual how to set up running <a href="https://github.com/apache/datasketches-characterization">characterization tests</a> remotely on a server (with an access to Linux command line) so that the characterization code sees local changes in the implementation of the sketches — here, we choose the <a href="https://github.com/apache/datasketches-java">Java implemenation</a> to experiment with. This allows us, for example, to verify a bug fix or test effects of changing some internal parameters of the sketches.</p>
<p>As a first step, check that the server has Java version 1.8, using <code class="highlighter-rouge">java -version</code>, as the DataSketches code requires JDK8. If not, install (or ask administrators to install) OpenJDK 8. Furthermore, we will need <a href="https://maven.apache.org/">Maven</a>, which may also be installed locally.</p>
<p>Next, start with cloning the required repositories into the desired location, including <a href="https://github.com/apache/datasketches-memory">DataSketches Memory</a> which is needed as a dependency. We will assume below that all repositories are in the same directory.</p>
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>$ git clone https://github.com/apache/datasketches-java.git
$ git clone https://github.com/apache/datasketches-characterization.git
$ git clone https://github.com/apache/datasketches-memory.git
</code></pre></div></div>
<p>Then go to the DataSketches Java component, possibly change the code as desired, and compile and install the Java component using Maven:</p>
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>$ mvn clean install
</code></pre></div></div>
<p>While the Java component gets compiled and installed in the <code class="highlighter-rouge">target/</code> subdirectory, the build may actually fail due to “Too many files with unapproved license” — this error should not affect the experiments in any way. When installing the Java component after some experimental changes, tests may need to be skipped during the installation (unless we update them), using option <code class="highlighter-rouge">-DskipTests=true</code>.</p>
<p>Compile and install the Memory component in the same way, that is using <code class="highlighter-rouge">mvn clean install</code> in directory <code class="highlighter-rouge">datasketches-memory</code>.</p>
<p>The crucial step is to make the characterization components use the local compiled Java component and not the one in the public repository. For this, we need to modify file <code class="highlighter-rouge">pom.xml</code> in the datasketches-characterization repository, which contains two <code class="highlighter-rouge">dependency</code> tags with element <code class="highlighter-rouge">artifactID</code> set to <code class="highlighter-rouge">datasketches-java</code>:</p>
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>&lt;dependency&gt;
&lt;groupId&gt;org.apache.datasketches&lt;/groupId&gt;
&lt;artifactId&gt;datasketches-java&lt;/artifactId&gt;
&lt;version&gt;${datasketches-java.version}&lt;/version&gt;
&lt;/dependency&gt;
&lt;!-- Dependency on Test code --&gt;
&lt;dependency&gt;
&lt;groupId&gt;org.apache.datasketches&lt;/groupId&gt;
&lt;artifactId&gt;datasketches-java&lt;/artifactId&gt;
&lt;version&gt;${datasketches-java.version}&lt;/version&gt;
&lt;type&gt;test-jar&lt;/type&gt;
&lt;/dependency&gt;
</code></pre></div></div>
<p>We modify both of them by adding the <code class="highlighter-rouge">scope</code> tag, set to <code class="highlighter-rouge">system</code>, and the <code class="highlighter-rouge">systemPath</code> tag as follows:</p>
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>&lt;dependency&gt;
&lt;groupId&gt;org.apache.datasketches&lt;/groupId&gt;
&lt;artifactId&gt;datasketches-java&lt;/artifactId&gt;
&lt;version&gt;${datasketches-java.version}&lt;/version&gt;
**&lt;scope&gt;system&lt;/scope&gt;**
**&lt;systemPath&gt;${basedir}/../datasketches-java/target/datasketches-java-1.4.0-SNAPSHOT.jar&lt;/systemPath&gt;**
&lt;/dependency&gt;
&lt;!-- Dependency on Test code --&gt;
&lt;dependency&gt;
&lt;groupId&gt;org.apache.datasketches&lt;/groupId&gt;
&lt;artifactId&gt;datasketches-java&lt;/artifactId&gt;
&lt;version&gt;${datasketches-java.version}&lt;/version&gt;
&lt;type&gt;test-jar&lt;/type&gt;
**&lt;scope&gt;system&lt;/scope&gt;**
**&lt;systemPath&gt;${basedir}/../datasketches-java/target/datasketches-java-1.4.0-SNAPSHOT-tests.jar&lt;/systemPath&gt;**
&lt;/dependency&gt;
</code></pre></div></div>
<p>The particular version of the Java component needs to be checked (see the <code class="highlighter-rouge">target/</code> subdirectory). <strong>Do not commit the modified pom.xml file.</strong></p>
<p>Having modified <code class="highlighter-rouge">pom.xml</code>, compile the characterization code using <code class="highlighter-rouge">mvn clean test</code> (no need to install this time). Some Maven warnings because of the modified <code class="highlighter-rouge">pom.xml</code> may appear, which we can nevertheless ignore.</p>
<p>Finally, choose a test to run, for example, <code class="highlighter-rouge">KllSketchAccuracyProfile</code>. After setting up the test configuration (in file <code class="highlighter-rouge">datasketches-characterization/src/main/resources/quantiles/KllSketchAccuracyJob.conf</code>) appropriately, it remains to run the test, for which we need to set the CLASSPATH enviroment variable before running <code class="highlighter-rouge">java</code> by executing the following in the datasketches-characterization directory (as above, the particular version of <code class="highlighter-rouge">datasketches-memory</code> and <code class="highlighter-rouge">datasketches-java</code> needs to be checked):</p>
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>$ export CLASSPATH="$CLASSPATH:$PWD/target/test-classes:$PWD/target/classes:$PWD/../datasketches-memory/target/datasketches-memory-1.3.0-SNAPSHOT.jar:$PWD/../datasketches-java/target/datasketches-java-1.4.0-SNAPSHOT.jar"
$ java -ea -Dfile.encoding=UTF-8 org.apache.datasketches.Job src/main/resources/quantiles/KllSketchAccuracyJob.conf
</code></pre></div></div>
<p>Then the test should run and when finishes, it writes the test results into a file in directory <code class="highlighter-rouge">datasketches-characterization</code>.</p>
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