Preview for PR #15 2cf6c29

Author: timtreis

pr-15/_images/2e89be7ab5f6f3e9ec0c3660503479d32fcf1e947cc2a0693d3592de6a1f6544.png

@@ -560,7 +560,8 @@ <h2>2. Colour and size still apply<a class="headerlink" href="#colour-and-size-s
 <div class="cell docutils container">
 <div class="cell_input docutils container">
 <div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="n">fig</span><span class="p">,</span> <span class="n">axes</span> <span class="o">=</span> <span class="n">plt</span><span class="o">.</span><span class="n">subplots</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="n">figsize</span><span class="o">=</span><span class="p">(</span><span class="mi">11</span><span class="p">,</span> <span class="mf">5.5</span><span class="p">))</span>
-<span class="n">crop</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span><span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">)</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">show</span><span class="p">(</span>
+<span class="c1"># Both panels share the same EPCAM scale, so we draw a single colourbar (right).</span>
+<span class="n">crop</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span><span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">,</span> <span class="n">colorbar</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">show</span><span class="p">(</span>
     <span class="n">ax</span><span class="o">=</span><span class="n">axes</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">title</span><span class="o">=</span><span class="s2">&quot;full geometry, colour = EPCAM&quot;</span>
 <span class="p">)</span>
 <span class="n">crop</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span>
@@ -571,7 +572,7 @@ <h2>2. Colour and size still apply<a class="headerlink" href="#colour-and-size-s
 </div>
 </div>
 <div class="cell_output docutils container">
-<img alt="../../_images/f664a4c304f2eeb3861e5f343b4193db75e6766f96fedfee843cb2e9b649fe53.png" src="../../_images/f664a4c304f2eeb3861e5f343b4193db75e6766f96fedfee843cb2e9b649fe53.png" />
+<img alt="../../_images/2e89be7ab5f6f3e9ec0c3660503479d32fcf1e947cc2a0693d3592de6a1f6544.png" src="../../_images/2e89be7ab5f6f3e9ec0c3660503479d32fcf1e947cc2a0693d3592de6a1f6544.png" />
 </div>
 </div>
 <p><code class="docutils literal notranslate"><span class="pre">size</span></code> sets the marker area (matplotlib’s scatter <code class="docutils literal notranslate"><span class="pre">s</span></code>), independent of the data.
@@ -582,7 +583,7 @@ <h2>2. Colour and size still apply<a class="headerlink" href="#colour-and-size-s
 <div class="cell_input docutils container">
 <div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="n">fig</span><span class="p">,</span> <span class="n">axes</span> <span class="o">=</span> <span class="n">plt</span><span class="o">.</span><span class="n">subplots</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="n">figsize</span><span class="o">=</span><span class="p">(</span><span class="mi">11</span><span class="p">,</span> <span class="mf">5.5</span><span class="p">))</span>
 <span class="n">crop</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span>
-    <span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">,</span> <span class="n">as_points</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">size</span><span class="o">=</span><span class="mi">8</span>
+    <span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">,</span> <span class="n">as_points</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">size</span><span class="o">=</span><span class="mi">8</span><span class="p">,</span> <span class="n">colorbar</span><span class="o">=</span><span class="kc">False</span>
 <span class="p">)</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">show</span><span class="p">(</span><span class="n">ax</span><span class="o">=</span><span class="n">axes</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">title</span><span class="o">=</span><span class="s2">&quot;size=8&quot;</span><span class="p">)</span>
 <span class="n">crop</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span>
     <span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">,</span> <span class="n">as_points</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">size</span><span class="o">=</span><span class="mi">80</span>
@@ -592,7 +593,7 @@ <h2>2. Colour and size still apply<a class="headerlink" href="#colour-and-size-s
 </div>
 </div>
 <div class="cell_output docutils container">
-<img alt="../../_images/6896d6f3e431546fb9535b1c3bf97ddb2576ee76eafb09f8b4ac8b47eccd7efc.png" src="../../_images/6896d6f3e431546fb9535b1c3bf97ddb2576ee76eafb09f8b4ac8b47eccd7efc.png" />
+<img alt="../../_images/7d5e0e9f388852ae2adba09bfae619e6fdb43ebe4c40b88edb23bdea02385df2.png" src="../../_images/7d5e0e9f388852ae2adba09bfae619e6fdb43ebe4c40b88edb23bdea02385df2.png" />
 </div>
 </div>
 </section>
@@ -693,10 +694,10 @@ <h2>4. The speed trade-off<a class="headerlink" href="#the-speed-trade-off" titl
 <div class="cell_output docutils container">
 <div class="output stream highlight-myst-ansi notranslate"><div class="highlight"><pre><span></span>N=   1000:  full   0.03s   as_points  0.01s   (4x)
 N=   5000:  full   0.13s   as_points  0.02s   (8x)
-N=  20000:  full   0.51s   as_points  0.04s   (13x)
-N=  50000:  full   1.26s   as_points  0.09s   (15x)
-N= 100000:  full   2.50s   as_points  0.17s   (15x)
-N= 167780:  full   4.19s   as_points  0.27s   (16x)
+N=  20000:  full   0.50s   as_points  0.04s   (13x)
+N=  50000:  full   1.23s   as_points  0.09s   (14x)
+N= 100000:  full   2.48s   as_points  0.17s   (15x)
+N= 167780:  full   4.15s   as_points  0.27s   (16x)
 </pre></div>
 </div>
 </div>
@@ -733,10 +734,10 @@ <h2>4. The speed trade-off<a class="headerlink" href="#the-speed-trade-off" titl
 </div>
 </div>
 <div class="cell_output docutils container">
-<div class="output stream highlight-myst-ansi notranslate"><div class="highlight"><pre><span></span>N=   424:  full mask  0.10s   as_points  0.09s
+<div class="output stream highlight-myst-ansi notranslate"><div class="highlight"><pre><span></span>N=   424:  full mask  0.09s   as_points  0.09s
 N=  5833:  full mask  0.10s   as_points  0.10s
 N= 18606:  full mask  0.12s   as_points  0.12s
-N= 39125:  full mask  0.16s   as_points  0.15s
+N= 39125:  full mask  0.15s   as_points  0.15s
 </pre></div>
 </div>
 </div>
@@ -762,7 +763,7 @@ <h2>4. The speed trade-off<a class="headerlink" href="#the-speed-trade-off" titl
 </div>
 </div>
 <div class="cell_output docutils container">
-<img alt="../../_images/827afb7dddaec5285fd0b9c78af6fd72749175941494151c9ae8f58aa57ca193.png" src="../../_images/827afb7dddaec5285fd0b9c78af6fd72749175941494151c9ae8f58aa57ca193.png" />
+<img alt="../../_images/de59cbe19573655e864703983ac44f0046efcf54ff6bc63f7788fab428a29a51.png" src="../../_images/de59cbe19573655e864703983ac44f0046efcf54ff6bc63f7788fab428a29a51.png" />
 </div>
 </div>
 <p>The two panels behave differently:</p>
@@ -790,27 +791,13 @@ <h2>5. Backend and the 50000 rule<a class="headerlink" href="#backend-and-the-50
 centroids (<code class="docutils literal notranslate"><span class="pre">AS_POINTS_DS_AUTO</span> <span class="pre">=</span> <span class="pre">50000</span></code>), because matplotlib’s per-glyph cost
 starts to dominate around there.</p></li>
 </ul>
+<p>The full-section <code class="docutils literal notranslate"><span class="pre">as_points</span></code> panel above used the default, so with 167780 cells
+it was already drawn by datashader. Passing <code class="docutils literal notranslate"><span class="pre">method=&quot;matplotlib&quot;</span></code> would force
+per-glyph scatter instead, and <code class="docutils literal notranslate"><span class="pre">method=&quot;datashader&quot;</span></code> forces the raster at any
+size.</p>
 <p>datashader aggregates and then shades, so it cannot represent one distinct random
 colour per cell, which is the default colouring of a labels element with no
-colour column. In that case it falls back to matplotlib with a warning. With a
-real colour column, as below, both backends work and differ only in appearance.</p>
-<div class="cell docutils container">
-<div class="cell_input docutils container">
-<div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="n">fig</span><span class="p">,</span> <span class="n">axes</span> <span class="o">=</span> <span class="n">plt</span><span class="o">.</span><span class="n">subplots</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="n">figsize</span><span class="o">=</span><span class="p">(</span><span class="mi">11</span><span class="p">,</span> <span class="mf">5.5</span><span class="p">))</span>
-<span class="n">sdata</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span>
-    <span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">,</span> <span class="n">as_points</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">method</span><span class="o">=</span><span class="s2">&quot;matplotlib&quot;</span>
-<span class="p">)</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">show</span><span class="p">(</span><span class="n">ax</span><span class="o">=</span><span class="n">axes</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">title</span><span class="o">=</span><span class="s2">&quot;matplotlib (167780 dots)&quot;</span><span class="p">)</span>
-<span class="n">sdata</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">render_shapes</span><span class="p">(</span>
-    <span class="s2">&quot;cell_circles&quot;</span><span class="p">,</span> <span class="n">color</span><span class="o">=</span><span class="s2">&quot;EPCAM&quot;</span><span class="p">,</span> <span class="n">cmap</span><span class="o">=</span><span class="s2">&quot;magma&quot;</span><span class="p">,</span> <span class="n">as_points</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">method</span><span class="o">=</span><span class="s2">&quot;datashader&quot;</span>
-<span class="p">)</span><span class="o">.</span><span class="n">pl</span><span class="o">.</span><span class="n">show</span><span class="p">(</span><span class="n">ax</span><span class="o">=</span><span class="n">axes</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span> <span class="n">title</span><span class="o">=</span><span class="s2">&quot;datashader&quot;</span><span class="p">)</span>
-<span class="n">fig</span><span class="o">.</span><span class="n">tight_layout</span><span class="p">()</span>
-</pre></div>
-</div>
-</div>
-<div class="cell_output docutils container">
-<img alt="../../_images/10477e56009357f96b8f3de3cd9b7de98cb94da4e83db5799c2872f143e83d71.png" src="../../_images/10477e56009357f96b8f3de3cd9b7de98cb94da4e83db5799c2872f143e83d71.png" />
-</div>
-</div>
+colour column. In that case it falls back to matplotlib with a warning.</p>
 </section>
 <section id="when-to-reach-for-as-points">
 <h2>When to reach for <code class="docutils literal notranslate"><span class="pre">as_points</span></code><a class="headerlink" href="#when-to-reach-for-as-points" title="Link to this heading">#</a></h2>