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| <section id="gandiva-expression-projector-and-filter"> |
| <h1>Gandiva Expression, Projector, and Filter<a class="headerlink" href="#gandiva-expression-projector-and-filter" title="Permalink to this heading">#</a></h1> |
| <section id="building-expressions"> |
| <h2>Building Expressions<a class="headerlink" href="#building-expressions" title="Permalink to this heading">#</a></h2> |
| <p>Gandiva provides a general expression representation where expressions are |
| represented by a tree of nodes. The expression trees are built using |
| <code class="xref py py-class docutils literal notranslate"><span class="pre">TreeExprBuilder</span></code>. The leaves of the expression tree are typically |
| field references, created by <code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeField()</span></code>, and |
| literal values, created by <code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeLiteral()</span></code>. Nodes |
| can be combined into more complex expression trees using:</p> |
| <ul class="simple"> |
| <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeFunction()</span></code> to create a function |
| node. (You can call <code class="xref py py-func docutils literal notranslate"><span class="pre">GetRegisteredFunctionSignatures()</span></code> to |
| get a list of valid function signatures.)</p></li> |
| <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeIf()</span></code> to create if-else logic.</p></li> |
| <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeAnd()</span></code> and <code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeOr()</span></code> |
| to create boolean expressions. (For “not”, use the <code class="docutils literal notranslate"><span class="pre">not(bool)</span></code> function in <code class="docutils literal notranslate"><span class="pre">MakeFunction</span></code>.)</p></li> |
| <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">TreeExprBuilder::MakeInExpressionInt32()</span></code> and the other “in expression” |
| functions to create set membership tests.</p></li> |
| </ul> |
| <p>Each of these functions create new composite nodes, which contain the leaf nodes |
| (literals and field references) or other composite nodes as children. By |
| composing these, you can create arbitrarily complex expression trees.</p> |
| <p>Once an expression tree is built, they are wrapped in either <code class="xref py py-class docutils literal notranslate"><span class="pre">Expression</span></code> |
| or <code class="xref py py-class docutils literal notranslate"><span class="pre">Condition</span></code>, depending on how they will be used. |
| <code class="docutils literal notranslate"><span class="pre">Expression</span></code> is used in projections while <code class="docutils literal notranslate"><span class="pre">Condition</span></code> is used in filters.</p> |
| <p>As an example, here is how to create an Expression representing <code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre">+</span> <span class="pre">3</span></code> and a |
| Condition representing <code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre"><</span> <span class="pre">3</span></code>:</p> |
| <div class="highlight-cpp notranslate"><div class="highlight"><pre><span></span><span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">Field</span><span class="o">></span><span class="w"> </span><span class="n">field_x_raw</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">field</span><span class="p">(</span><span class="s">"x"</span><span class="p">,</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">int32</span><span class="p">());</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Node</span><span class="o">></span><span class="w"> </span><span class="n">field_x</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">TreeExprBuilder</span><span class="o">::</span><span class="n">MakeField</span><span class="p">(</span><span class="n">field_x_raw</span><span class="p">);</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Node</span><span class="o">></span><span class="w"> </span><span class="n">literal_3</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">TreeExprBuilder</span><span class="o">::</span><span class="n">MakeLiteral</span><span class="p">(</span><span class="mi">3</span><span class="p">);</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">Field</span><span class="o">></span><span class="w"> </span><span class="n">field_result</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">field</span><span class="p">(</span><span class="s">"result"</span><span class="p">,</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">int32</span><span class="p">());</span> |
| |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Node</span><span class="o">></span><span class="w"> </span><span class="n">add_node</span><span class="w"> </span><span class="o">=</span> |
| <span class="w"> </span><span class="n">TreeExprBuilder</span><span class="o">::</span><span class="n">MakeFunction</span><span class="p">(</span><span class="s">"add"</span><span class="p">,</span><span class="w"> </span><span class="p">{</span><span class="n">field_x</span><span class="p">,</span><span class="w"> </span><span class="n">literal_3</span><span class="p">},</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">int32</span><span class="p">());</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Expression</span><span class="o">></span><span class="w"> </span><span class="n">expression</span><span class="w"> </span><span class="o">=</span> |
| <span class="w"> </span><span class="n">TreeExprBuilder</span><span class="o">::</span><span class="n">MakeExpression</span><span class="p">(</span><span class="n">add_node</span><span class="p">,</span><span class="w"> </span><span class="n">field_result</span><span class="p">);</span> |
| |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Node</span><span class="o">></span><span class="w"> </span><span class="n">less_than_node</span><span class="w"> </span><span class="o">=</span> |
| <span class="w"> </span><span class="n">TreeExprBuilder</span><span class="o">::</span><span class="n">MakeFunction</span><span class="p">(</span><span class="s">"less_than"</span><span class="p">,</span><span class="w"> </span><span class="p">{</span><span class="n">field_x</span><span class="p">,</span><span class="w"> </span><span class="n">literal_3</span><span class="p">},</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">boolean</span><span class="p">());</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Condition</span><span class="o">></span><span class="w"> </span><span class="n">condition</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">TreeExprBuilder</span><span class="o">::</span><span class="n">MakeCondition</span><span class="p">(</span><span class="n">less_than_node</span><span class="p">);</span> |
| </pre></div> |
| </div> |
| </section> |
| <section id="projectors-and-filters"> |
| <h2>Projectors and Filters<a class="headerlink" href="#projectors-and-filters" title="Permalink to this heading">#</a></h2> |
| <p>Gandiva’s two execution kernels are <code class="xref py py-class docutils literal notranslate"><span class="pre">Projector</span></code> and |
| <code class="xref py py-class docutils literal notranslate"><span class="pre">Filter</span></code>. <code class="docutils literal notranslate"><span class="pre">Projector</span></code> consumes a record batch and projects |
| into a new record batch. <code class="docutils literal notranslate"><span class="pre">Filter</span></code> consumes a record batch and produces a |
| <code class="xref py py-class docutils literal notranslate"><span class="pre">SelectionVector</span></code> containing the indices that matched the condition.</p> |
| <p>For both <code class="docutils literal notranslate"><span class="pre">Projector</span></code> and <code class="docutils literal notranslate"><span class="pre">Filter</span></code>, optimization of the expression IR happens |
| when creating instances. They are compiled against a static schema, so the |
| schema of the record batches must be known at this point.</p> |
| <p>Continuing with the <code class="docutils literal notranslate"><span class="pre">expression</span></code> and <code class="docutils literal notranslate"><span class="pre">condition</span></code> created in the previous |
| section, here is an example of creating a Projector and a Filter:</p> |
| <div class="highlight-cpp notranslate"><div class="highlight"><pre><span></span><span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">Schema</span><span class="o">></span><span class="w"> </span><span class="n">input_schema</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">schema</span><span class="p">({</span><span class="n">field_x_raw</span><span class="p">});</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">Schema</span><span class="o">></span><span class="w"> </span><span class="n">output_schema</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">schema</span><span class="p">({</span><span class="n">field_result</span><span class="p">});</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Projector</span><span class="o">></span><span class="w"> </span><span class="n">projector</span><span class="p">;</span> |
| <span class="n">Status</span><span class="w"> </span><span class="n">status</span><span class="p">;</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">vector</span><span class="o"><</span><span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Expression</span><span class="o">>></span><span class="w"> </span><span class="n">expressions</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{</span><span class="n">expression</span><span class="p">};</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Projector</span><span class="o">::</span><span class="n">Make</span><span class="p">(</span><span class="n">input_schema</span><span class="p">,</span><span class="w"> </span><span class="n">expressions</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">projector</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">Filter</span><span class="o">></span><span class="w"> </span><span class="n">filter</span><span class="p">;</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Filter</span><span class="o">::</span><span class="n">Make</span><span class="p">(</span><span class="n">input_schema</span><span class="p">,</span><span class="w"> </span><span class="n">condition</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">filter</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| </pre></div> |
| </div> |
| <p>Once a Projector or Filter is created, it can be evaluated on Arrow record batches. |
| These execution kernels are single-threaded on their own, but are designed to be |
| reused to process distinct record batches in parallel.</p> |
| <section id="evaluating-projections"> |
| <h3>Evaluating projections<a class="headerlink" href="#evaluating-projections" title="Permalink to this heading">#</a></h3> |
| <p>Execution is performed with <code class="xref py py-func docutils literal notranslate"><span class="pre">Projector::Evaluate()</span></code>. This outputs |
| a vector of arrays, which can be passed along with the output schema to |
| <code class="xref py py-func docutils literal notranslate"><span class="pre">arrow::RecordBatch::Make()</span></code>.</p> |
| <div class="highlight-cpp notranslate"><div class="highlight"><pre><span></span><span class="k">auto</span><span class="w"> </span><span class="n">pool</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">default_memory_pool</span><span class="p">();</span> |
| <span class="kt">int</span><span class="w"> </span><span class="n">num_records</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">4</span><span class="p">;</span> |
| <span class="n">arrow</span><span class="o">::</span><span class="n">Int32Builder</span><span class="w"> </span><span class="n">builder</span><span class="p">;</span> |
| <span class="kt">int32_t</span><span class="w"> </span><span class="n">values</span><span class="p">[</span><span class="mi">4</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{</span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="mi">2</span><span class="p">,</span><span class="w"> </span><span class="mi">3</span><span class="p">,</span><span class="w"> </span><span class="mi">4</span><span class="p">};</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">builder</span><span class="p">.</span><span class="n">AppendValues</span><span class="p">(</span><span class="n">values</span><span class="p">,</span><span class="w"> </span><span class="mi">4</span><span class="p">));</span> |
| <span class="n">ARROW_ASSIGN_OR_RAISE</span><span class="p">(</span><span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">Array</span><span class="o">></span><span class="w"> </span><span class="n">array</span><span class="p">,</span><span class="w"> </span><span class="n">builder</span><span class="p">.</span><span class="n">Finish</span><span class="p">());</span> |
| <span class="k">auto</span><span class="w"> </span><span class="n">in_batch</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">RecordBatch</span><span class="o">::</span><span class="n">Make</span><span class="p">(</span><span class="n">input_schema</span><span class="p">,</span><span class="w"> </span><span class="n">num_records</span><span class="p">,</span><span class="w"> </span><span class="p">{</span><span class="n">array</span><span class="p">});</span> |
| |
| <span class="n">arrow</span><span class="o">::</span><span class="n">ArrayVector</span><span class="w"> </span><span class="n">outputs</span><span class="p">;</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">projector</span><span class="o">-></span><span class="n">Evaluate</span><span class="p">(</span><span class="o">*</span><span class="n">in_batch</span><span class="p">,</span><span class="w"> </span><span class="n">pool</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">outputs</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">RecordBatch</span><span class="o">></span><span class="w"> </span><span class="n">result</span><span class="w"> </span><span class="o">=</span> |
| <span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">RecordBatch</span><span class="o">::</span><span class="n">Make</span><span class="p">(</span><span class="n">output_schema</span><span class="p">,</span><span class="w"> </span><span class="n">outputs</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">-></span><span class="n">length</span><span class="p">(),</span><span class="w"> </span><span class="n">outputs</span><span class="p">);</span> |
| </pre></div> |
| </div> |
| </section> |
| <section id="evaluating-filters"> |
| <h3>Evaluating filters<a class="headerlink" href="#evaluating-filters" title="Permalink to this heading">#</a></h3> |
| <p><code class="xref py py-func docutils literal notranslate"><span class="pre">Filter::Evaluate()</span></code> produces <code class="xref py py-class docutils literal notranslate"><span class="pre">SelectionVector</span></code>, |
| a vector of row indices that matched the filter condition. The selection vector |
| is a wrapper around an arrow integer array, parameterized by bitwidth. When |
| creating the selection vector (you must initialize it <em>before</em> passing to |
| <code class="docutils literal notranslate"><span class="pre">Evaluate()</span></code>), you must choose the bitwidth, which determines the max index |
| value it can hold, and the max number of slots, which determines how many indices |
| it may contain. In general, the max number of slots should be set to your batch |
| size and the bitwidth the smallest integer size that can represent all integers |
| less than the batch size. For example, if your batch size is 100k, set the |
| maximum number of slots to 100k and the bitwidth to 32 (since 2^16 = 64k which |
| would be too small).</p> |
| <p>Once <code class="docutils literal notranslate"><span class="pre">Evaluate()</span></code> has been run and the <code class="xref py py-class docutils literal notranslate"><span class="pre">SelectionVector</span></code> is |
| populated, use the <code class="xref py py-func docutils literal notranslate"><span class="pre">SelectionVector::ToArray()</span></code> method to get |
| the underlying array and then <code class="xref py py-func docutils literal notranslate"><span class="pre">::arrow::compute::Take()</span></code> to materialize the |
| output record batch.</p> |
| <div class="highlight-cpp notranslate"><div class="highlight"><pre><span></span><span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">gandiva</span><span class="o">::</span><span class="n">SelectionVector</span><span class="o">></span><span class="w"> </span><span class="n">result_indices</span><span class="p">;</span> |
| <span class="c1">// Use 16-bit integers for indices. Result can be no longer than input size,</span> |
| <span class="c1">// so use batch num_rows as max_slots.</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">gandiva</span><span class="o">::</span><span class="n">SelectionVector</span><span class="o">::</span><span class="n">MakeInt16</span><span class="p">(</span><span class="cm">/*max_slots=*/</span><span class="n">in_batch</span><span class="o">-></span><span class="n">num_rows</span><span class="p">(),</span><span class="w"> </span><span class="n">pool</span><span class="p">,</span> |
| <span class="w"> </span><span class="o">&</span><span class="n">result_indices</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">filter</span><span class="o">-></span><span class="n">Evaluate</span><span class="p">(</span><span class="o">*</span><span class="n">in_batch</span><span class="p">,</span><span class="w"> </span><span class="n">result_indices</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| <span class="n">std</span><span class="o">::</span><span class="n">shared_ptr</span><span class="o"><</span><span class="n">arrow</span><span class="o">::</span><span class="n">Array</span><span class="o">></span><span class="w"> </span><span class="n">take_indices</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">result_indices</span><span class="o">-></span><span class="n">ToArray</span><span class="p">();</span> |
| <span class="n">Datum</span><span class="w"> </span><span class="n">maybe_batch</span><span class="p">;</span> |
| <span class="n">ARROW_ASSIGN_OR_RAISE</span><span class="p">(</span><span class="n">maybe_batch</span><span class="p">,</span> |
| <span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">compute</span><span class="o">::</span><span class="n">Take</span><span class="p">(</span><span class="n">Datum</span><span class="p">(</span><span class="n">in_batch</span><span class="p">),</span><span class="w"> </span><span class="n">Datum</span><span class="p">(</span><span class="n">take_indices</span><span class="p">),</span> |
| <span class="w"> </span><span class="n">TakeOptions</span><span class="o">::</span><span class="n">NoBoundsCheck</span><span class="p">()));</span> |
| <span class="n">result</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">maybe_batch</span><span class="p">.</span><span class="n">record_batch</span><span class="p">();</span> |
| </pre></div> |
| </div> |
| </section> |
| <section id="evaluating-projections-and-filters"> |
| <h3>Evaluating projections and filters<a class="headerlink" href="#evaluating-projections-and-filters" title="Permalink to this heading">#</a></h3> |
| <p>Finally, you can also project while apply a selection vector, with |
| <code class="xref py py-func docutils literal notranslate"><span class="pre">Projector::Evaluate()</span></code>. To do so, first make sure to initialize the |
| <code class="xref py py-class docutils literal notranslate"><span class="pre">Projector</span></code> with <code class="xref py py-func docutils literal notranslate"><span class="pre">SelectionVector::GetMode()</span></code> so that the projector |
| compiles with the correct bitwidth. Then you can pass the |
| <code class="xref py py-class docutils literal notranslate"><span class="pre">SelectionVector</span></code> into the <code class="xref py py-func docutils literal notranslate"><span class="pre">Projector::Evaluate()</span></code> method.</p> |
| <div class="highlight-cpp notranslate"><div class="highlight"><pre><span></span><span class="c1">// Make sure the projector is compiled for the appropriate selection vector mode</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Projector</span><span class="o">::</span><span class="n">Make</span><span class="p">(</span><span class="n">input_schema</span><span class="p">,</span><span class="w"> </span><span class="n">expressions</span><span class="p">,</span><span class="w"> </span><span class="n">result_indices</span><span class="o">-></span><span class="n">GetMode</span><span class="p">(),</span> |
| <span class="w"> </span><span class="n">ConfigurationBuilder</span><span class="o">::</span><span class="n">DefaultConfiguration</span><span class="p">(),</span><span class="w"> </span><span class="o">&</span><span class="n">projector</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| |
| <span class="n">arrow</span><span class="o">::</span><span class="n">ArrayVector</span><span class="w"> </span><span class="n">outputs_filtered</span><span class="p">;</span> |
| <span class="n">status</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">projector</span><span class="o">-></span><span class="n">Evaluate</span><span class="p">(</span><span class="o">*</span><span class="n">in_batch</span><span class="p">,</span><span class="w"> </span><span class="n">result_indices</span><span class="p">.</span><span class="n">get</span><span class="p">(),</span><span class="w"> </span><span class="n">pool</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">outputs_filtered</span><span class="p">);</span> |
| <span class="n">ARROW_RETURN_NOT_OK</span><span class="p">(</span><span class="n">status</span><span class="p">);</span> |
| |
| <span class="n">result</span><span class="w"> </span><span class="o">=</span> |
| <span class="w"> </span><span class="n">arrow</span><span class="o">::</span><span class="n">RecordBatch</span><span class="o">::</span><span class="n">Make</span><span class="p">(</span><span class="n">output_schema</span><span class="p">,</span><span class="w"> </span><span class="n">outputs</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">-></span><span class="n">length</span><span class="p">(),</span><span class="w"> </span><span class="n">outputs_filtered</span><span class="p">);</span> |
| </pre></div> |
| </div> |
| </section> |
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