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Fix html link

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Nicolas Rougier 2015-02-26 18:32:36 +01:00
parent ef0df80871
commit 24744cc581
2 changed files with 54 additions and 12 deletions
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@ -26,7 +26,7 @@ is:</p>
print np.nonzero([1,2,0,0,4,0])
</pre>
<p>Here is what the page looks like so far:
<a class="reference external" href="http://www.loria.fr/~rougier/teaching/numpy.100/index.html">http://www.loria.fr/~rougier/teaching/numpy.100/index.html</a></p>
<a class="reference external" href="http://http://www.labri.fr/perso/nrougier/teaching/numpy.100/index.html">http://http://www.labri.fr/perso/nrougier/teaching/numpy.100/index.html</a></p>
<div class="note">
<p class="first admonition-title">Note</p>
<p class="last">The level names came from an old-game (Dungeon Master)</p>
@ -439,6 +439,27 @@ np.bincount(A) == C ?</p>
<span class="keyword">print</span> <span class="name">moving_average</span><span class="punctuation">(</span><span class="name">Z</span><span class="punctuation">,</span> <span class="name">n</span><span class="operator">=</span><span class="literal number integer">3</span><span class="punctuation">)</span>
</pre>
</li>
<li><p class="first">How to get the documentation of the numpy add function from the command line ?</p>
<pre class="code bash literal-block">
python -c <span class="literal string double">&quot;import numpy; numpy.info(numpy.add)&quot;</span>
</pre>
</li>
<li><p class="first">How to negate a boolean, or to change the sign of a float inplace ?</p>
</li>
</ol>
<blockquote>
<pre class="code python literal-block">
<span class="comment"># Author: Nathaniel J. Smith</span>
<span class="name">Z</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">randint</span><span class="punctuation">(</span><span class="literal number integer">0</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">,</span><span class="literal number integer">100</span><span class="punctuation">)</span>
<span class="name">np</span><span class="operator">.</span><span class="name">logical_not</span><span class="punctuation">(</span><span class="name">arr</span><span class="punctuation">,</span> <span class="name">out</span><span class="operator">=</span><span class="name">arr</span><span class="punctuation">)</span>
<span class="name">Z</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number float">1.0</span><span class="punctuation">,</span><span class="literal number float">1.0</span><span class="punctuation">,</span><span class="literal number integer">100</span><span class="punctuation">)</span>
<span class="name">np</span><span class="operator">.</span><span class="name">negative</span><span class="punctuation">(</span><span class="name">arr</span><span class="punctuation">,</span> <span class="name">out</span><span class="operator">=</span><span class="name">arr</span><span class="punctuation">)</span>
</pre>
</blockquote>
<ol class="arabic simple" start="7">
<li></li>
</ol>
</div>
<div class="section" id="artisan">
@ -473,20 +494,20 @@ np.bincount(A) == C ?</p>
compute distance from p to each line i (P0[i],P1[i]) ?</p>
<pre class="code python literal-block">
<span class="keyword">def</span> <span class="name function">distance</span><span class="punctuation">(</span><span class="name">P0</span><span class="punctuation">,</span> <span class="name">P1</span><span class="punctuation">,</span> <span class="name">p</span><span class="punctuation">):</span>
<span class="name">T</span> <span class="operator">=</span> <span class="name">P1</span> <span class="operator">-</span> <span class="name">P0</span>
<span class="name">L</span> <span class="operator">=</span> <span class="punctuation">(</span><span class="name">T</span><span class="operator">**</span><span class="literal number integer">2</span><span class="punctuation">)</span><span class="operator">.</span><span class="name">sum</span><span class="punctuation">(</span><span class="name">axis</span><span class="operator">=</span><span class="literal number integer">1</span><span class="punctuation">)</span>
<span class="name">U</span> <span class="operator">=</span> <span class="operator">-</span><span class="punctuation">((</span><span class="name">P0</span><span class="punctuation">[:,</span><span class="literal number integer">0</span><span class="punctuation">]</span><span class="operator">-</span><span class="name">p</span><span class="punctuation">[</span><span class="literal number integer">0</span><span class="punctuation">])</span><span class="operator">*</span><span class="name">T</span><span class="punctuation">[:,</span><span class="literal number integer">0</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="punctuation">(</span><span class="name">P0</span><span class="punctuation">[:,</span><span class="literal number integer">1</span><span class="punctuation">]</span><span class="operator">-</span><span class="name">p</span><span class="punctuation">[</span><span class="literal number integer">1</span><span class="punctuation">])</span><span class="operator">*</span><span class="name">T</span><span class="punctuation">[:,</span><span class="literal number integer">1</span><span class="punctuation">])</span> <span class="operator">/</span> <span class="name">L</span>
<span class="name">U</span> <span class="operator">=</span> <span class="name">U</span><span class="operator">.</span><span class="name">reshape</span><span class="punctuation">(</span><span class="name builtin">len</span><span class="punctuation">(</span><span class="name">U</span><span class="punctuation">),</span><span class="literal number integer">1</span><span class="punctuation">)</span>
<span class="name">D</span> <span class="operator">=</span> <span class="name">P0</span> <span class="operator">+</span> <span class="name">U</span><span class="operator">*</span><span class="name">T</span> <span class="operator">-</span> <span class="name">p</span>
<span class="keyword">return</span> <span class="name">np</span><span class="operator">.</span><span class="name">sqrt</span><span class="punctuation">((</span><span class="name">D</span><span class="operator">**</span><span class="literal number integer">2</span><span class="punctuation">)</span><span class="operator">.</span><span class="name">sum</span><span class="punctuation">(</span><span class="name">axis</span><span class="operator">=</span><span class="literal number integer">1</span><span class="punctuation">))</span>
<span class="name">T</span> <span class="operator">=</span> <span class="name">P1</span> <span class="operator">-</span> <span class="name">P0</span>
<span class="name">L</span> <span class="operator">=</span> <span class="punctuation">(</span><span class="name">T</span><span class="operator">**</span><span class="literal number integer">2</span><span class="punctuation">)</span><span class="operator">.</span><span class="name">sum</span><span class="punctuation">(</span><span class="name">axis</span><span class="operator">=</span><span class="literal number integer">1</span><span class="punctuation">)</span>
<span class="name">U</span> <span class="operator">=</span> <span class="operator">-</span><span class="punctuation">((</span><span class="name">P0</span><span class="punctuation">[:,</span><span class="literal number integer">0</span><span class="punctuation">]</span><span class="operator">-</span><span class="name">p</span><span class="punctuation">[</span><span class="operator">...</span><span class="punctuation">,</span><span class="literal number integer">0</span><span class="punctuation">])</span><span class="operator">*</span><span class="name">T</span><span class="punctuation">[:,</span><span class="literal number integer">0</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="punctuation">(</span><span class="name">P0</span><span class="punctuation">[:,</span><span class="literal number integer">1</span><span class="punctuation">]</span><span class="operator">-</span><span class="name">p</span><span class="punctuation">[</span><span class="operator">...</span><span class="punctuation">,</span><span class="literal number integer">1</span><span class="punctuation">])</span><span class="operator">*</span><span class="name">T</span><span class="punctuation">[:,</span><span class="literal number integer">1</span><span class="punctuation">])</span> <span class="operator">/</span> <span class="name">L</span>
<span class="name">U</span> <span class="operator">=</span> <span class="name">U</span><span class="operator">.</span><span class="name">reshape</span><span class="punctuation">(</span><span class="name builtin">len</span><span class="punctuation">(</span><span class="name">U</span><span class="punctuation">),</span><span class="literal number integer">1</span><span class="punctuation">)</span>
<span class="name">D</span> <span class="operator">=</span> <span class="name">P0</span> <span class="operator">+</span> <span class="name">U</span><span class="operator">*</span><span class="name">T</span> <span class="operator">-</span> <span class="name">p</span>
<span class="keyword">return</span> <span class="name">np</span><span class="operator">.</span><span class="name">sqrt</span><span class="punctuation">((</span><span class="name">D</span><span class="operator">**</span><span class="literal number integer">2</span><span class="punctuation">)</span><span class="operator">.</span><span class="name">sum</span><span class="punctuation">(</span><span class="name">axis</span><span class="operator">=</span><span class="literal number integer">1</span><span class="punctuation">))</span>
<span class="name">P0</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">10</span><span class="punctuation">,(</span><span class="literal number integer">100</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">))</span>
<span class="name">P1</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">10</span><span class="punctuation">,(</span><span class="literal number integer">100</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">))</span>
<span class="name">p</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">10</span><span class="punctuation">,(</span> <span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">))</span>
<span class="name">P0</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">10</span><span class="punctuation">,(</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">))</span>
<span class="name">P1</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">10</span><span class="punctuation">,(</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">))</span>
<span class="name">p</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">uniform</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">10</span><span class="punctuation">,</span><span class="literal number integer">10</span><span class="punctuation">,(</span> <span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">))</span>
<span class="keyword">print</span> <span class="name">distance</span><span class="punctuation">(</span><span class="name">P0</span><span class="punctuation">,</span> <span class="name">P1</span><span class="punctuation">,</span> <span class="name">p</span><span class="punctuation">)</span>
</pre>
</li>
<li><p class="first">Consider 2 sets of points P0,P1 describing lines (2d) and a set of point P,
<li><p class="first">Consider 2 sets of points P0,P1 describing lines (2d) and a set of points P,
how to compute distance from each point j (P[j]) to each line i (P0[i],P1[i]) ?</p>
<pre class="code python literal-block">
<span class="name">Answer</span> <span class="name">needed</span> <span class="name">actually</span>
@ -627,6 +648,27 @@ How to compute the sum of of the p matrix products at once ? (result has shape (
<span class="keyword">print</span> <span class="name">uZ</span>
</pre>
</li>
<li><p class="first">How to implement the Game of Life using numpy arrays ?</p>
<pre class="code python literal-block">
<span class="comment"># Author: Nicolas Rougier</span>
<span class="keyword">def</span> <span class="name function">iterate</span><span class="punctuation">(</span><span class="name">Z</span><span class="punctuation">):</span>
<span class="comment"># Count neighbours</span>
<span class="name">N</span> <span class="operator">=</span> <span class="punctuation">(</span><span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">0</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">2</span><span class="punctuation">,</span><span class="literal number integer">0</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">2</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">0</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">2</span><span class="punctuation">,</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">0</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">2</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">:]</span> <span class="operator">+</span>
<span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">0</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">2</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">:]</span> <span class="operator">+</span>
<span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">2</span><span class="punctuation">:</span> <span class="punctuation">,</span><span class="literal number integer">0</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">2</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">2</span><span class="punctuation">:</span> <span class="punctuation">,</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">]</span> <span class="operator">+</span> <span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">2</span><span class="punctuation">:</span> <span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">:])</span>
<span class="comment"># Apply rules</span>
<span class="name">birth</span> <span class="operator">=</span> <span class="punctuation">(</span><span class="name">N</span><span class="operator">==</span><span class="literal number integer">3</span><span class="punctuation">)</span> <span class="operator">&amp;</span> <span class="punctuation">(</span><span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">]</span><span class="operator">==</span><span class="literal number integer">0</span><span class="punctuation">)</span>
<span class="name">survive</span> <span class="operator">=</span> <span class="punctuation">((</span><span class="name">N</span><span class="operator">==</span><span class="literal number integer">2</span><span class="punctuation">)</span> <span class="operator">|</span> <span class="punctuation">(</span><span class="name">N</span><span class="operator">==</span><span class="literal number integer">3</span><span class="punctuation">))</span> <span class="operator">&amp;</span> <span class="punctuation">(</span><span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">]</span><span class="operator">==</span><span class="literal number integer">1</span><span class="punctuation">)</span>
<span class="name">Z</span><span class="punctuation">[</span><span class="operator">...</span><span class="punctuation">]</span> <span class="operator">=</span> <span class="literal number integer">0</span>
<span class="name">Z</span><span class="punctuation">[</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">,</span><span class="literal number integer">1</span><span class="punctuation">:</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">][</span><span class="name">birth</span> <span class="operator">|</span> <span class="name">survive</span><span class="punctuation">]</span> <span class="operator">=</span> <span class="literal number integer">1</span>
<span class="keyword">return</span> <span class="name">Z</span>
<span class="name">Z</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">random</span><span class="operator">.</span><span class="name">randint</span><span class="punctuation">(</span><span class="literal number integer">0</span><span class="punctuation">,</span><span class="literal number integer">2</span><span class="punctuation">,(</span><span class="literal number integer">50</span><span class="punctuation">,</span><span class="literal number integer">50</span><span class="punctuation">))</span>
<span class="keyword">for</span> <span class="name">i</span> <span class="operator word">in</span> <span class="name builtin">range</span><span class="punctuation">(</span><span class="literal number integer">100</span><span class="punctuation">):</span> <span class="name">Z</span> <span class="operator">=</span> <span class="name">iterate</span><span class="punctuation">(</span><span class="name">Z</span><span class="punctuation">)</span>
</pre>
</li>
</ol>
</div>
<div class="section" id="archmaster">

2
README.rst
View File

@ -22,7 +22,7 @@ is:
Here is what the page looks like so far:
http://www.loria.fr/~rougier/teaching/numpy.100/index.html
http://http://www.labri.fr/perso/nrougier/teaching/numpy.100/index.html
.. Note:: The level names came from an old-game (Dungeon Master)