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<spanid="sphx-glr-gallery-api-sankey-basics-py"></span><h1>The Sankey class<aclass="headerlink" href="#the-sankey-class" title="Permalink to this headline">¶</a></h1>
<p>Demonstrate the Sankey class by producing three basic diagrams.</p>
<spanclass="kn">from</span><spanclass="nn">matplotlib.sankey</span><spanclass="kn">import</span><ahref="../../api/sankey_api.html#matplotlib.sankey.Sankey" title="View documentation for matplotlib.sankey.Sankey"><spanclass="n">Sankey</span></a>
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<p>Example 1 – Mostly defaults</p>
<p>This demonstrates how to create a simple diagram by implicitly calling the
Sankey.add() method and by appending finish() to the call to the class.</p>
<divclass="highlight-python notranslate"><divclass="highlight"><pre><span></span><ahref="../../api/sankey_api.html#matplotlib.sankey.Sankey" title="View documentation for matplotlib.sankey.Sankey"><spanclass="n">Sankey</span></a><spanclass="p">(</span><spanclass="n">flows</span><spanclass="o">=</span><spanclass="p">[</span><spanclass="mf">0.25</span><spanclass="p">,</span><spanclass="mf">0.15</span><spanclass="p">,</span><spanclass="mf">0.60</span><spanclass="p">,</span><spanclass="o">-</span><spanclass="mf">0.20</span><spanclass="p">,</span><spanclass="o">-</span><spanclass="mf">0.15</span><spanclass="p">,</span><spanclass="o">-</span><spanclass="mf">0.05</span><spanclass="p">,</span><spanclass="o">-</span><spanclass="mf">0.50</span><spanclass="p">,</span><spanclass="o">-</span><spanclass="mf">0.10</span><spanclass="p">],</span>
<ahref="../../api/_as_gen/matplotlib.pyplot.title.html#matplotlib.pyplot.title" title="View documentation for matplotlib.pyplot.title"><spanclass="n">plt</span><spanclass="o">.</span><spanclass="n">title</span></a><spanclass="p">(</span><spanclass="s2">"The default settings produce a diagram like this."</span><spanclass="p">)</span>
<spanclass="n">title</span><spanclass="o">=</span><spanclass="s2">"Flow Diagram of a Widget"</span><spanclass="p">)</span>
<spanclass="n">sankey</span><spanclass="o">=</span><ahref="../../api/sankey_api.html#matplotlib.sankey.Sankey" title="View documentation for matplotlib.sankey.Sankey"><spanclass="n">Sankey</span></a><spanclass="p">(</span><spanclass="n">ax</span><spanclass="o">=</span><spanclass="n">ax</span><spanclass="p">,</span><spanclass="n">scale</span><spanclass="o">=</span><spanclass="mf">0.01</span><spanclass="p">,</span><spanclass="n">offset</span><spanclass="o">=</span><spanclass="mf">0.2</span><spanclass="p">,</span><spanclass="n">head_angle</span><spanclass="o">=</span><spanclass="mi">180</span><spanclass="p">,</span>
<spanclass="n">patchlabel</span><spanclass="o">=</span><spanclass="s2">"Widget</span><spanclass="se">\n</span><spanclass="s2">A"</span><spanclass="p">)</span><spanclass="c1"># Arguments to matplotlib.patches.PathPatch()</span>
<spanclass="n">sankey</span><spanclass="o">=</span><ahref="../../api/sankey_api.html#matplotlib.sankey.Sankey" title="View documentation for matplotlib.sankey.Sankey"><spanclass="n">Sankey</span></a><spanclass="p">(</span><spanclass="n">ax</span><spanclass="o">=</span><spanclass="n">ax</span><spanclass="p">,</span><spanclass="n">unit</span><spanclass="o">=</span><spanclass="bp">None</span><spanclass="p">)</span>
<ahref="../../api/_as_gen/matplotlib.pyplot.legend.html#matplotlib.pyplot.legend" title="View documentation for matplotlib.pyplot.legend"><spanclass="n">plt</span><spanclass="o">.</span><spanclass="n">legend</span></a><spanclass="p">(</span><spanclass="n">loc</span><spanclass="o">=</span><spanclass="s1">'best'</span><spanclass="p">)</span>