<h4 dir="auto">Description:</h4>
<p dir="auto">I experience <code class="notranslate">Segmentation Fault</code> when executing a script. I am unable to detect what exactly causes the crash, nor to deliver a minimal reproducing code. However, I can share the <code class="notranslate">backtrace</code> from <code class="notranslate">gdb</code>:</p>
<h4 dir="auto">Error Message:</h4>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)"><pre class="notranslate"><code class="notranslate">Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)
</code></pre></div>
<h4 dir="auto">Backtrace:</h4>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="from /home/samuele/.conda/envs/rl-new/lib/python3.7/site-packages/scipy/linalg/_flapack.cpython-37m-x86_64-linux-gnu.so
#1  0x00005555556cc61b in _PyObject_FastCallKeywords ()
#2  0x0000555555728a79 in _PyEval_EvalFrameDefault ()
#3  0x0000555555669059 in _PyEval_EvalCodeWithName ()
#4  0x00005555556cb2a5 in _PyFunction_FastCallKeywords ()
#5  0x0000555555723a66 in _PyEval_EvalFrameDefault ()
#6  0x0000555555669059 in _PyEval_EvalCodeWithName ()
#7  0x00005555556cb2a5 in _PyFunction_FastCallKeywords ()
#8  0x0000555555727e6e in _PyEval_EvalFrameDefault ()
#9  0x00005555556cb07b in _PyFunction_FastCallKeywords ()
#10 0x0000555555723a66 in _PyEval_EvalFrameDefault ()
#11 0x0000555555669919 in _PyEval_EvalCodeWithName ()
#12 0x000055555566a134 in _PyFunction_FastCallDict ()
#13 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#14 0x0000555555669919 in _PyEval_EvalCodeWithName ()
#15 0x000055555566a134 in _PyFunction_FastCallDict ()
#16 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#17 0x0000555555669059 in _PyEval_EvalCodeWithName ()
#18 0x00005555556cb307 in _PyFunction_FastCallKeywords ()
#19 0x0000555555723a66 in _PyEval_EvalFrameDefault ()
#20 0x000055555566a06b in _PyFunction_FastCallDict ()
---Type &lt;return&gt; to continue, or q &lt;return&gt; to quit---
#21 0x0000555555680a03 in _PyObject_Call_Prepend ()
#22 0x00005555556c3baa in slot_tp_call ()
#23 0x00005555556758d2 in PyObject_Call ()
#24 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#25 0x0000555555669059 in _PyEval_EvalCodeWithName ()
#26 0x000055555566a134 in _PyFunction_FastCallDict ()
#27 0x0000555555680a03 in _PyObject_Call_Prepend ()
#28 0x00005555556c3baa in slot_tp_call ()
#29 0x00005555556758d2 in PyObject_Call ()
#30 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#31 0x0000555555669059 in _PyEval_EvalCodeWithName ()
#32 0x000055555566a134 in _PyFunction_FastCallDict ()
#33 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#34 0x00005555556cb07b in _PyFunction_FastCallKeywords ()
#35 0x00005555557238b0 in _PyEval_EvalFrameDefault ()
#36 0x00005555556cb07b in _PyFunction_FastCallKeywords ()
#37 0x00005555557238b0 in _PyEval_EvalFrameDefault ()
#38 0x000055555566a06b in _PyFunction_FastCallDict ()
#39 0x0000555555680a03 in _PyObject_Call_Prepend ()
#40 0x00005555556758d2 in PyObject_Call ()
#41 0x0000555555775ef7 in t_bootstrap ()
#42 0x00007ffff79266db in start_thread (arg=0x7fff117fa700)
    at pthread_create.c:463
---Type &lt;return&gt; to continue, or q &lt;return&gt; to quit---
#43 0x00007ffff764f71f in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95"><pre class="notranslate"><code class="notranslate">from /home/samuele/.conda/envs/rl-new/lib/python3.7/site-packages/scipy/linalg/_flapack.cpython-37m-x86_64-linux-gnu.so
#1  0x00005555556cc61b in _PyObject_FastCallKeywords ()
#2  0x0000555555728a79 in _PyEval_EvalFrameDefault ()
#3  0x0000555555669059 in _PyEval_EvalCodeWithName ()
#4  0x00005555556cb2a5 in _PyFunction_FastCallKeywords ()
#5  0x0000555555723a66 in _PyEval_EvalFrameDefault ()
#6  0x0000555555669059 in _PyEval_EvalCodeWithName ()
#7  0x00005555556cb2a5 in _PyFunction_FastCallKeywords ()
#8  0x0000555555727e6e in _PyEval_EvalFrameDefault ()
#9  0x00005555556cb07b in _PyFunction_FastCallKeywords ()
#10 0x0000555555723a66 in _PyEval_EvalFrameDefault ()
#11 0x0000555555669919 in _PyEval_EvalCodeWithName ()
#12 0x000055555566a134 in _PyFunction_FastCallDict ()
#13 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#14 0x0000555555669919 in _PyEval_EvalCodeWithName ()
#15 0x000055555566a134 in _PyFunction_FastCallDict ()
#16 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#17 0x0000555555669059 in _PyEval_EvalCodeWithName ()
#18 0x00005555556cb307 in _PyFunction_FastCallKeywords ()
#19 0x0000555555723a66 in _PyEval_EvalFrameDefault ()
#20 0x000055555566a06b in _PyFunction_FastCallDict ()
---Type &lt;return&gt; to continue, or q &lt;return&gt; to quit---
#21 0x0000555555680a03 in _PyObject_Call_Prepend ()
#22 0x00005555556c3baa in slot_tp_call ()
#23 0x00005555556758d2 in PyObject_Call ()
#24 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#25 0x0000555555669059 in _PyEval_EvalCodeWithName ()
#26 0x000055555566a134 in _PyFunction_FastCallDict ()
#27 0x0000555555680a03 in _PyObject_Call_Prepend ()
#28 0x00005555556c3baa in slot_tp_call ()
#29 0x00005555556758d2 in PyObject_Call ()
#30 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#31 0x0000555555669059 in _PyEval_EvalCodeWithName ()
#32 0x000055555566a134 in _PyFunction_FastCallDict ()
#33 0x00005555557251ab in _PyEval_EvalFrameDefault ()
#34 0x00005555556cb07b in _PyFunction_FastCallKeywords ()
#35 0x00005555557238b0 in _PyEval_EvalFrameDefault ()
#36 0x00005555556cb07b in _PyFunction_FastCallKeywords ()
#37 0x00005555557238b0 in _PyEval_EvalFrameDefault ()
#38 0x000055555566a06b in _PyFunction_FastCallDict ()
#39 0x0000555555680a03 in _PyObject_Call_Prepend ()
#40 0x00005555556758d2 in PyObject_Call ()
#41 0x0000555555775ef7 in t_bootstrap ()
#42 0x00007ffff79266db in start_thread (arg=0x7fff117fa700)
    at pthread_create.c:463
---Type &lt;return&gt; to continue, or q &lt;return&gt; to quit---
#43 0x00007ffff764f71f in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
</code></pre></div>
<h4 dir="auto">Scipy/Numpy/Python version information:</h4>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="sys==1.5.2 
scipy==1.19.2 
sys.version_info(major=3, minor=7, micro=0, releaselevel='final', serial=0)"><pre class="notranslate"><code class="notranslate">sys==1.5.2 
scipy==1.19.2 
sys.version_info(major=3, minor=7, micro=0, releaselevel='final', serial=0)
</code></pre></div>
<h4 dir="auto">System Information:</h4>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="Ubuntu 18.84.5 LTS 64-bit
AMD® Ryzen 9 3900x 12-core processor × 24
GNOME 3.28.2"><pre class="notranslate"><code class="notranslate">Ubuntu 18.84.5 LTS 64-bit
AMD® Ryzen 9 3900x 12-core processor × 24
GNOME 3.28.2
</code></pre></div>
<p dir="auto"><em>Original ticket <a href="http://projects.scipy.org/scipy/ticket/1421" rel="nofollow">http://projects.scipy.org/scipy/ticket/1421</a> on 2011-04-08 by trac user schwarz, assigned to <a class="user-mention notranslate" data-hovercard-type="user" data-hovercard-url="/users/pv/hovercard" data-octo-click="hovercard-link-click" data-octo-dimensions="link_type:self" href="https://github.com/pv">@pv</a>.</em></p>
<p dir="auto">Problem:<br>
the Documentation [http://docs.scipy.org/doc/scipy-0.9.0/reference/generated/scipy.stats.poisson.html#scipy.stats.poisson]<br>
states that there are the methods:<br>
pdf(x, mu, loc=0, scale=1)  Probability density function.<br>
fit(data, mu, loc=0, scale=1)   Parameter estimates for generic data.</p>
<p dir="auto">but this is not true.</p>
<p dir="auto">Steps to reproduce:</p>
<ol dir="auto">
<li>install scipy from <a href="http://sourceforge.net/projects/scipy/files/scipy/0.9.0/scipy-0.9.0.tar.gz/download" rel="nofollow">http://sourceforge.net/projects/scipy/files/scipy/0.9.0/scipy-0.9.0.tar.gz/download</a></li>
</ol>
<p dir="auto">2.) run python with:</p>
<blockquote>
<p dir="auto">import scipy<br>
print scipy.stats.poisson.fit<br>
print scipy.stats.poisson.pdf</p>
</blockquote>
<p dir="auto">3.) get output:<br>
AttributeError: 'poisson_gen' object has no attribute 'fit'<br>
AttributeError: 'poisson_gen' object has no attribute 'pdf'</p>
<p dir="auto">4.) check scipy version:</p>
<blockquote>
<p dir="auto">print scipy.<strong>version</strong><br>
0.9.0</p>
</blockquote>