<h3 dir="auto">Bug report</h3>
<p dir="auto"><strong>Bug summary</strong></p>
<p dir="auto">When plotting scatter data with symlog y axis, the data in the linear part are not plotted</p>
<div class="highlight highlight-source-python notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="import matplotlib.pyplot as plt
import numpy as np
x = np.linspace(0,1, 1000)
y = (np.random.random((len(x),))-0.5)*100
c = (np.random.random((len(x),))-0.5)*10
plt.scatter(x,y,c=c,marker='o',lw=0)
plt.yscale('symlog',linthreshy=10)
plt.show()"><pre class="notranslate"><span class="pl-k">import</span> <span class="pl-s1">matplotlib</span>.<span class="pl-s1">pyplot</span> <span class="pl-k">as</span> <span class="pl-s1">plt</span>
<span class="pl-k">import</span> <span class="pl-s1">numpy</span> <span class="pl-k">as</span> <span class="pl-s1">np</span>
<span class="pl-s1">x</span> <span class="pl-c1">=</span> <span class="pl-s1">np</span>.<span class="pl-en">linspace</span>(<span class="pl-c1">0</span>,<span class="pl-c1">1</span>, <span class="pl-c1">1000</span>)
<span class="pl-s1">y</span> <span class="pl-c1">=</span> (<span class="pl-s1">np</span>.<span class="pl-s1">random</span>.<span class="pl-en">random</span>((<span class="pl-en">len</span>(<span class="pl-s1">x</span>),))<span class="pl-c1">-</span><span class="pl-c1">0.5</span>)<span class="pl-c1">*</span><span class="pl-c1">100</span>
<span class="pl-s1">c</span> <span class="pl-c1">=</span> (<span class="pl-s1">np</span>.<span class="pl-s1">random</span>.<span class="pl-en">random</span>((<span class="pl-en">len</span>(<span class="pl-s1">x</span>),))<span class="pl-c1">-</span><span class="pl-c1">0.5</span>)<span class="pl-c1">*</span><span class="pl-c1">10</span>
<span class="pl-s1">plt</span>.<span class="pl-en">scatter</span>(<span class="pl-s1">x</span>,<span class="pl-s1">y</span>,<span class="pl-s1">c</span><span class="pl-c1">=</span><span class="pl-s1">c</span>,<span class="pl-s1">marker</span><span class="pl-c1">=</span><span class="pl-s">'o'</span>,<span class="pl-s1">lw</span><span class="pl-c1">=</span><span class="pl-c1">0</span>)
<span class="pl-s1">plt</span>.<span class="pl-en">yscale</span>(<span class="pl-s">'symlog'</span>,<span class="pl-s1">linthreshy</span><span class="pl-c1">=</span><span class="pl-c1">10</span>)
<span class="pl-s1">plt</span>.<span class="pl-en">show</span>()</pre></div>
<p dir="auto"><strong>Actual outcome</strong></p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/11966765/63227234-9a0dc580-c1a1-11e9-9c14-c1177ff9c071.png"><img src="https://user-images.githubusercontent.com/11966765/63227234-9a0dc580-c1a1-11e9-9c14-c1177ff9c071.png" alt="image" style="max-width: 100%;"></a></p>
<p dir="auto"><strong>Matplotlib version</strong></p>
<ul dir="auto">
<li>Operating system:</li>
<li>Matplotlib version: 3.1.0</li>
<li>Matplotlib backend (<code class="notranslate">print(matplotlib.get_backend())</code>): Qt5Agg</li>
<li>Python version: 3.7</li>
</ul>
<p dir="auto">installed via conda, default channel</p>
<h3 dir="auto">Bug report</h3>
<p dir="auto"><strong>Bug summary</strong></p>
<p dir="auto">Since I updated to 3.1.0, symlog looses some points, at least when drawing a scatter plot</p>
<p dir="auto"><strong>Code for reproduction</strong></p>
<div class="highlight highlight-source-python notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="import matplotlib.pyplot as plt
import numpy as np
 
x = [1.0000e+00, 2.0000e+00, 3.0000e+00, 4.0000e+00, 5.0000e+00, 6.0000e+00, 7.0000e+00, 8.0000e+00, 9.0000e+00, 1.0000e+01, 1.1000e+01, 1.2000e+01, 1.3000e+01, 1.4000e+01, 1.5000e+01, 1.6000e+01, 1.7000e+01, 1.8000e+01, 1.9000e+01, 2.0000e+01, 2.1000e+01, 2.2000e+01, 2.3000e+01, 2.4000e+01, 2.5000e+01, 2.6000e+01, 2.7000e+01, 2.8000e+01, 2.9000e+01, 3.0000e+01, 3.1000e+01, 3.2000e+01, 3.3000e+01, 3.5000e+01, 3.7000e+01, 3.8000e+01, 3.9000e+01, 4.0000e+01, 4.2000e+01, 4.3000e+01, 4.5000e+01, 4.6000e+01, 4.8000e+01, 5.0000e+01, 5.2000e+01, 5.5000e+01, 5.7000e+01, 6.0000e+01, 6.1000e+01, 6.3000e+01, 6.7000e+01, 6.8000e+01, 7.1000e+01, 7.6000e+01, 7.7000e+01, 8.0000e+01, 8.6000e+01, 8.7000e+01, 8.8000e+01, 9.1000e+01, 9.8000e+01, 9.9000e+01, 1.0000e+02, 1.0400e+02, 1.1400e+02, 1.1600e+02, 1.2100e+02, 1.3300e+02, 1.3400e+02, 1.3500e+02, 1.4200e+02, 1.5600e+02, 1.5700e+02, 1.5900e+02, 1.6700e+02, 1.8600e+02, 1.8700e+02, 1.8800e+02, 1.9000e+02, 2.0000e+02, 2.2600e+02, 2.3000e+02, 2.3100e+02, 2.4600e+02, 2.9200e+02, 2.9500e+02, 2.9900e+02, 3.0000e+02, 3.2000e+02, 4.4200e+02, 4.4500e+02, 4.5200e+02, 4.5700e+02, 4.8500e+02, 1.0645e+04, 1.1602e+04, 1.3856e+04, 1.6537e+04, 1.7642e+04, 2.2227e+04]

y = [0.57583333, 0.73833333, 0.81666667, 0.86016667, 0.88616667, 0.90266667, 0.91416667, 0.92333333, 0.93033333, 0.93633333, 0.94133333, 0.946, 0.94966667, 0.95333333, 0.95633333, 0.95866667, 0.96133333, 0.9635, 0.9655, 0.96683333, 0.96866667, 0.97016667, 0.97166667, 0.97266667, 0.97383333, 0.97483333, 0.9758, 0.97633333, 0.9775, 0.97783333, 0.979, 0.9795, 0.97983333, 0.98083333, 0.9818, 0.982, 0.982, 0.983, 0.983, 0.984, 0.984, 0.985, 0.985, 0.986, 0.986, 0.987, 0.987, 0.988, 0.988, 0.988, 0.989, 0.989, 0.989, 0.99, 0.99, 0.99, 0.991, 0.991, 0.991, 0.991, 0.992, 0.992, 0.992, 0.992, 0.993, 0.993, 0.993, 0.994, 0.994, 0.994, 0.994, 0.995, 0.995, 0.995, 0.995, 0.996, 0.996, 0.996, 0.996, 0.996, 0.997, 0.997, 0.997, 0.997, 0.998, 0.998, 0.998, 0.998, 0.998, 0.999, 0.999, 0.999, 0.999, 0.999, 1., 1., 1., 1., 1., 1. ]

plt.xscale(&quot;symlog&quot;)
plt.scatter(x, y)
plt.show()"><pre class="notranslate"><span class="pl-k">import</span> <span class="pl-s1">matplotlib</span>.<span class="pl-s1">pyplot</span> <span class="pl-k">as</span> <span class="pl-s1">plt</span>
<span class="pl-k">import</span> <span class="pl-s1">numpy</span> <span class="pl-k">as</span> <span class="pl-s1">np</span>
 
<span class="pl-s1">x</span> <span class="pl-c1">=</span> [<span class="pl-c1">1.0000e+00</span>, <span class="pl-c1">2.0000e+00</span>, <span class="pl-c1">3.0000e+00</span>, <span class="pl-c1">4.0000e+00</span>, <span class="pl-c1">5.0000e+00</span>, <span class="pl-c1">6.0000e+00</span>, <span class="pl-c1">7.0000e+00</span>, <span class="pl-c1">8.0000e+00</span>, <span class="pl-c1">9.0000e+00</span>, <span class="pl-c1">1.0000e+01</span>, <span class="pl-c1">1.1000e+01</span>, <span class="pl-c1">1.2000e+01</span>, <span class="pl-c1">1.3000e+01</span>, <span class="pl-c1">1.4000e+01</span>, <span class="pl-c1">1.5000e+01</span>, <span class="pl-c1">1.6000e+01</span>, <span class="pl-c1">1.7000e+01</span>, <span class="pl-c1">1.8000e+01</span>, <span class="pl-c1">1.9000e+01</span>, <span class="pl-c1">2.0000e+01</span>, <span class="pl-c1">2.1000e+01</span>, <span class="pl-c1">2.2000e+01</span>, <span class="pl-c1">2.3000e+01</span>, <span class="pl-c1">2.4000e+01</span>, <span class="pl-c1">2.5000e+01</span>, <span class="pl-c1">2.6000e+01</span>, <span class="pl-c1">2.7000e+01</span>, <span class="pl-c1">2.8000e+01</span>, <span class="pl-c1">2.9000e+01</span>, <span class="pl-c1">3.0000e+01</span>, <span class="pl-c1">3.1000e+01</span>, <span class="pl-c1">3.2000e+01</span>, <span class="pl-c1">3.3000e+01</span>, <span class="pl-c1">3.5000e+01</span>, <span class="pl-c1">3.7000e+01</span>, <span class="pl-c1">3.8000e+01</span>, <span class="pl-c1">3.9000e+01</span>, <span class="pl-c1">4.0000e+01</span>, <span class="pl-c1">4.2000e+01</span>, <span class="pl-c1">4.3000e+01</span>, <span class="pl-c1">4.5000e+01</span>, <span class="pl-c1">4.6000e+01</span>, <span class="pl-c1">4.8000e+01</span>, <span class="pl-c1">5.0000e+01</span>, <span class="pl-c1">5.2000e+01</span>, <span class="pl-c1">5.5000e+01</span>, <span class="pl-c1">5.7000e+01</span>, <span class="pl-c1">6.0000e+01</span>, <span class="pl-c1">6.1000e+01</span>, <span class="pl-c1">6.3000e+01</span>, <span class="pl-c1">6.7000e+01</span>, <span class="pl-c1">6.8000e+01</span>, <span class="pl-c1">7.1000e+01</span>, <span class="pl-c1">7.6000e+01</span>, <span class="pl-c1">7.7000e+01</span>, <span class="pl-c1">8.0000e+01</span>, <span class="pl-c1">8.6000e+01</span>, <span class="pl-c1">8.7000e+01</span>, <span class="pl-c1">8.8000e+01</span>, <span class="pl-c1">9.1000e+01</span>, <span class="pl-c1">9.8000e+01</span>, <span class="pl-c1">9.9000e+01</span>, <span class="pl-c1">1.0000e+02</span>, <span class="pl-c1">1.0400e+02</span>, <span class="pl-c1">1.1400e+02</span>, <span class="pl-c1">1.1600e+02</span>, <span class="pl-c1">1.2100e+02</span>, <span class="pl-c1">1.3300e+02</span>, <span class="pl-c1">1.3400e+02</span>, <span class="pl-c1">1.3500e+02</span>, <span class="pl-c1">1.4200e+02</span>, <span class="pl-c1">1.5600e+02</span>, <span class="pl-c1">1.5700e+02</span>, <span class="pl-c1">1.5900e+02</span>, <span class="pl-c1">1.6700e+02</span>, <span class="pl-c1">1.8600e+02</span>, <span class="pl-c1">1.8700e+02</span>, <span class="pl-c1">1.8800e+02</span>, <span class="pl-c1">1.9000e+02</span>, <span class="pl-c1">2.0000e+02</span>, <span class="pl-c1">2.2600e+02</span>, <span class="pl-c1">2.3000e+02</span>, <span class="pl-c1">2.3100e+02</span>, <span class="pl-c1">2.4600e+02</span>, <span class="pl-c1">2.9200e+02</span>, <span class="pl-c1">2.9500e+02</span>, <span class="pl-c1">2.9900e+02</span>, <span class="pl-c1">3.0000e+02</span>, <span class="pl-c1">3.2000e+02</span>, <span class="pl-c1">4.4200e+02</span>, <span class="pl-c1">4.4500e+02</span>, <span class="pl-c1">4.5200e+02</span>, <span class="pl-c1">4.5700e+02</span>, <span class="pl-c1">4.8500e+02</span>, <span class="pl-c1">1.0645e+04</span>, <span class="pl-c1">1.1602e+04</span>, <span class="pl-c1">1.3856e+04</span>, <span class="pl-c1">1.6537e+04</span>, <span class="pl-c1">1.7642e+04</span>, <span class="pl-c1">2.2227e+04</span>]

<span class="pl-s1">y</span> <span class="pl-c1">=</span> [<span class="pl-c1">0.57583333</span>, <span class="pl-c1">0.73833333</span>, <span class="pl-c1">0.81666667</span>, <span class="pl-c1">0.86016667</span>, <span class="pl-c1">0.88616667</span>, <span class="pl-c1">0.90266667</span>, <span class="pl-c1">0.91416667</span>, <span class="pl-c1">0.92333333</span>, <span class="pl-c1">0.93033333</span>, <span class="pl-c1">0.93633333</span>, <span class="pl-c1">0.94133333</span>, <span class="pl-c1">0.946</span>, <span class="pl-c1">0.94966667</span>, <span class="pl-c1">0.95333333</span>, <span class="pl-c1">0.95633333</span>, <span class="pl-c1">0.95866667</span>, <span class="pl-c1">0.96133333</span>, <span class="pl-c1">0.9635</span>, <span class="pl-c1">0.9655</span>, <span class="pl-c1">0.96683333</span>, <span class="pl-c1">0.96866667</span>, <span class="pl-c1">0.97016667</span>, <span class="pl-c1">0.97166667</span>, <span class="pl-c1">0.97266667</span>, <span class="pl-c1">0.97383333</span>, <span class="pl-c1">0.97483333</span>, <span class="pl-c1">0.9758</span>, <span class="pl-c1">0.97633333</span>, <span class="pl-c1">0.9775</span>, <span class="pl-c1">0.97783333</span>, <span class="pl-c1">0.979</span>, <span class="pl-c1">0.9795</span>, <span class="pl-c1">0.97983333</span>, <span class="pl-c1">0.98083333</span>, <span class="pl-c1">0.9818</span>, <span class="pl-c1">0.982</span>, <span class="pl-c1">0.982</span>, <span class="pl-c1">0.983</span>, <span class="pl-c1">0.983</span>, <span class="pl-c1">0.984</span>, <span class="pl-c1">0.984</span>, <span class="pl-c1">0.985</span>, <span class="pl-c1">0.985</span>, <span class="pl-c1">0.986</span>, <span class="pl-c1">0.986</span>, <span class="pl-c1">0.987</span>, <span class="pl-c1">0.987</span>, <span class="pl-c1">0.988</span>, <span class="pl-c1">0.988</span>, <span class="pl-c1">0.988</span>, <span class="pl-c1">0.989</span>, <span class="pl-c1">0.989</span>, <span class="pl-c1">0.989</span>, <span class="pl-c1">0.99</span>, <span class="pl-c1">0.99</span>, <span class="pl-c1">0.99</span>, <span class="pl-c1">0.991</span>, <span class="pl-c1">0.991</span>, <span class="pl-c1">0.991</span>, <span class="pl-c1">0.991</span>, <span class="pl-c1">0.992</span>, <span class="pl-c1">0.992</span>, <span class="pl-c1">0.992</span>, <span class="pl-c1">0.992</span>, <span class="pl-c1">0.993</span>, <span class="pl-c1">0.993</span>, <span class="pl-c1">0.993</span>, <span class="pl-c1">0.994</span>, <span class="pl-c1">0.994</span>, <span class="pl-c1">0.994</span>, <span class="pl-c1">0.994</span>, <span class="pl-c1">0.995</span>, <span class="pl-c1">0.995</span>, <span class="pl-c1">0.995</span>, <span class="pl-c1">0.995</span>, <span class="pl-c1">0.996</span>, <span class="pl-c1">0.996</span>, <span class="pl-c1">0.996</span>, <span class="pl-c1">0.996</span>, <span class="pl-c1">0.996</span>, <span class="pl-c1">0.997</span>, <span class="pl-c1">0.997</span>, <span class="pl-c1">0.997</span>, <span class="pl-c1">0.997</span>, <span class="pl-c1">0.998</span>, <span class="pl-c1">0.998</span>, <span class="pl-c1">0.998</span>, <span class="pl-c1">0.998</span>, <span class="pl-c1">0.998</span>, <span class="pl-c1">0.999</span>, <span class="pl-c1">0.999</span>, <span class="pl-c1">0.999</span>, <span class="pl-c1">0.999</span>, <span class="pl-c1">0.999</span>, <span class="pl-c1">1.</span>, <span class="pl-c1">1.</span>, <span class="pl-c1">1.</span>, <span class="pl-c1">1.</span>, <span class="pl-c1">1.</span>, <span class="pl-c1">1.</span> ]

<span class="pl-s1">plt</span>.<span class="pl-en">xscale</span>(<span class="pl-s">"symlog"</span>)
<span class="pl-s1">plt</span>.<span class="pl-en">scatter</span>(<span class="pl-s1">x</span>, <span class="pl-s1">y</span>)
<span class="pl-s1">plt</span>.<span class="pl-en">show</span>()</pre></div>
<p dir="auto"><strong>Actual outcome</strong><br>
Using 3.1.0<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/248961/57986525-64f4b880-7a76-11e9-941f-4dea5da9f722.png"><img src="https://user-images.githubusercontent.com/248961/57986525-64f4b880-7a76-11e9-941f-4dea5da9f722.png" alt="310" style="max-width: 100%;"></a></p>
<p dir="auto"><strong>Expected outcome</strong><br>
Using 3.0.3<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/248961/57986520-57d7c980-7a76-11e9-9b2d-0e23e2adcd65.png"><img src="https://user-images.githubusercontent.com/248961/57986520-57d7c980-7a76-11e9-9b2d-0e23e2adcd65.png" alt="303" style="max-width: 100%;"></a></p>
<p dir="auto">Especially look at the Y axis, we lost the 0.5 value and 0.7 too. Worst, I think (not clear here in this picture) that the points are shifted from the actual X values</p>
<p dir="auto"><strong>Matplotlib version</strong></p>
<ul dir="auto">
<li>Operating system: Ubuntu 18.04 LTS</li>
<li>Matplotlib version:  3.1.0</li>
<li>Matplotlib backend : TkAgg</li>
<li>Python version: 3.6.7<br>
Installed with pip3</li>
</ul>