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| <li class="toctree-l3"><a class="reference internal" href="#datasketches.theta_sketch.get_num_retained"><code class="docutils literal notranslate"><span class="pre">theta_sketch.get_num_retained()</span></code></a></li> |
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| <li class="toctree-l3"><a class="reference internal" href="#datasketches.theta_sketch.get_theta"><code class="docutils literal notranslate"><span class="pre">theta_sketch.get_theta()</span></code></a></li> |
| <li class="toctree-l3"><a class="reference internal" href="#datasketches.theta_sketch.get_theta64"><code class="docutils literal notranslate"><span class="pre">theta_sketch.get_theta64()</span></code></a></li> |
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| <li class="toctree-l3"><a class="reference internal" href="#datasketches.theta_sketch.is_ordered"><code class="docutils literal notranslate"><span class="pre">theta_sketch.is_ordered()</span></code></a></li> |
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| |
| <section id="theta-sketch"> |
| <h1>Theta Sketch<a class="headerlink" href="#theta-sketch" title="Link to this heading"></a></h1> |
| <p>The <em>Theta Sketch</em> sketch is a space-efficient method for estimating cardinalities of sets. |
| It can also easily handle set operations (such as union, intersection, difference) while maintaining good accuarcy.</p> |
| <dl class="py class"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch"> |
| <em class="property"><span class="pre">class</span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">_datasketches.</span></span><span class="sig-name descname"><span class="pre">theta_sketch</span></span><a class="headerlink" href="#datasketches.theta_sketch" title="Link to this definition"></a></dt> |
| <dd><dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_estimate"> |
| <span class="sig-name descname"><span class="pre">get_estimate</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">float</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_estimate" title="Link to this definition"></a></dt> |
| <dd><p>Estimate of the distinct count of the input stream</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_lower_bound"> |
| <span class="sig-name descname"><span class="pre">get_lower_bound</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em>, <em class="sig-param"><span class="n"><span class="pre">num_std_devs</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><span class="pre">int</span></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">float</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_lower_bound" title="Link to this definition"></a></dt> |
| <dd><p>Returns an approximate lower bound on the estimate at standard deviations in {1, 2, 3}</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_num_retained"> |
| <span class="sig-name descname"><span class="pre">get_num_retained</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">int</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_num_retained" title="Link to this definition"></a></dt> |
| <dd><p>Returns the number of items currently in the sketch</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_seed_hash"> |
| <span class="sig-name descname"><span class="pre">get_seed_hash</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">int</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_seed_hash" title="Link to this definition"></a></dt> |
| <dd><p>Returns a hash of the seed used in the sketch</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_theta"> |
| <span class="sig-name descname"><span class="pre">get_theta</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">float</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_theta" title="Link to this definition"></a></dt> |
| <dd><p>Returns theta (effective sampling rate) as a fraction from 0 to 1</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_theta64"> |
| <span class="sig-name descname"><span class="pre">get_theta64</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">int</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_theta64" title="Link to this definition"></a></dt> |
| <dd><p>Returns theta as 64-bit value</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.get_upper_bound"> |
| <span class="sig-name descname"><span class="pre">get_upper_bound</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em>, <em class="sig-param"><span class="n"><span class="pre">num_std_devs</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><span class="pre">int</span></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">float</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.get_upper_bound" title="Link to this definition"></a></dt> |
| <dd><p>Returns an approximate upper bound on the estimate at standard deviations in {1, 2, 3}</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.is_empty"> |
| <span class="sig-name descname"><span class="pre">is_empty</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">bool</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.is_empty" title="Link to this definition"></a></dt> |
| <dd><p>Returns True if the sketch is empty, otherwise False</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.is_estimation_mode"> |
| <span class="sig-name descname"><span class="pre">is_estimation_mode</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">bool</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.is_estimation_mode" title="Link to this definition"></a></dt> |
| <dd><p>Returns True if sketch is in estimation mode, otherwise False</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.is_ordered"> |
| <span class="sig-name descname"><span class="pre">is_ordered</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">bool</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.is_ordered" title="Link to this definition"></a></dt> |
| <dd><p>Returns True if the sketch entries are sorted, otherwise False</p> |
| </dd></dl> |
| |
| <dl class="py method"> |
| <dt class="sig sig-object py" id="datasketches.theta_sketch.to_string"> |
| <span class="sig-name descname"><span class="pre">to_string</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">self</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="#datasketches.theta_sketch" title="_datasketches.theta_sketch"><span class="pre">_datasketches.theta_sketch</span></a></span></em>, <em class="sig-param"><span class="n"><span class="pre">print_items</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><span class="pre">bool</span></span><span class="w"> </span><span class="o"><span class="pre">=</span></span><span class="w"> </span><span class="default_value"><span class="pre">False</span></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><span class="pre">str</span></span></span><a class="headerlink" href="#datasketches.theta_sketch.to_string" title="Link to this definition"></a></dt> |
| <dd><p>Produces a string summary of the sketch</p> |
| </dd></dl> |
| |
| </dd></dl> |
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