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<div class="section" id="compute-functions">
<span id="compute"></span><h1>Compute Functions<a class="headerlink" href="#compute-functions" title="Permalink to this headline">ΒΆ</a></h1>
<p>Arrow supports logical compute operations over inputs of possibly
varying types. Many compute functions support both array (chunked or not)
and scalar inputs, but some will mandate either. For example,
the <code class="docutils literal notranslate"><span class="pre">fill_null</span></code> function requires its second input to be a scalar,
while <code class="docutils literal notranslate"><span class="pre">sort_indices</span></code> requires its first and only input to
be an array.</p>
<p>Below are a few simple examples:</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">pyarrow</span> <span class="k">as</span> <span class="nn">pa</span>
<span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">pyarrow.compute</span> <span class="k">as</span> <span class="nn">pc</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span> <span class="o">=</span> <span class="n">pa</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">pc</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">a</span><span class="p">)</span>
<span class="go">&lt;pyarrow.Int64Scalar: 7&gt;</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span> <span class="o">=</span> <span class="n">pa</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="mi">4</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">8</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">pc</span><span class="o">.</span><span class="n">equal</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">)</span>
<span class="go">&lt;pyarrow.lib.BooleanArray object at 0x7f686e4eef30&gt;</span>
<span class="go">[</span>
<span class="go"> false,</span>
<span class="go"> true,</span>
<span class="go"> true,</span>
<span class="go"> false</span>
<span class="go">]</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="p">,</span> <span class="n">y</span> <span class="o">=</span> <span class="n">pa</span><span class="o">.</span><span class="n">scalar</span><span class="p">(</span><span class="mf">7.8</span><span class="p">),</span> <span class="n">pa</span><span class="o">.</span><span class="n">scalar</span><span class="p">(</span><span class="mf">9.3</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">pc</span><span class="o">.</span><span class="n">multiply</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">y</span><span class="p">)</span>
<span class="go">&lt;pyarrow.DoubleScalar: 72.54&gt;</span>
</pre></div>
</div>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="../cpp/compute.html#compute-function-list"><span class="std std-ref">Available compute functions (C++ documentation)</span></a>.</p>
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