Added exercise with warning level

This commit is contained in:
Nicolas P. Rougier
2016-07-14 20:21:23 -05:00
parent 503be76295
commit f1059bd9c7
2 changed files with 31 additions and 6 deletions

View File

@@ -233,15 +233,26 @@ python -c <span class="literal string double">&quot;import numpy; numpy.info(num
<span class="keyword">print</span><span class="punctuation">(</span><span class="name">np</span><span class="operator">.</span><span class="name">intersect1d</span><span class="punctuation">(</span><span class="name">Z1</span><span class="punctuation">,</span><span class="name">Z2</span><span class="punctuation">))</span>
</pre>
</li>
<li><p class="first">How to ignore all numpy warnings (not recommended)? (★☆☆)</p>
<pre class="code python literal-block">
<span class="comment single"># Suicide mode on</span>
<span class="name">defaults</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">seterr</span><span class="punctuation">(</span><span class="name builtin">all</span><span class="operator">=</span><span class="literal string double">&quot;ignore&quot;</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">ones</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">0</span>
<span class="comment single"># Back to sanity</span>
<span class="name">np</span><span class="operator">.</span><span class="name">seterr</span><span class="punctuation">(</span><span class="operator">**</span><span class="name">defaults</span><span class="punctuation">)</span>
</pre>
</li>
<li><p class="first">Is the following expressions true? (★☆☆)</p>
<pre class="code python literal-block">
<span class="name">np</span><span class="operator">.</span><span class="name">sqrt</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">np</span><span class="operator">.</span><span class="name">emath</span><span class="operator">.</span><span class="name">sqrt</span><span class="punctuation">(</span><span class="operator">-</span><span class="literal number integer">1</span><span class="punctuation">)</span>
</pre>
</li>
<li><p class="first">How to get the current date ? (★☆☆)</p>
<li><p class="first">How to get the dates of yesterday, today and tomorrow? (★☆☆)</p>
<pre class="code python literal-block">
<span class="name">np</span><span class="operator">.</span><span class="name">datetime64</span><span class="punctuation">(</span><span class="literal string single">'today'</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span>
<span class="name">np</span><span class="operator">.</span><span class="name">datetime64</span><span class="punctuation">(</span><span class="literal string single">'now'</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span>
<span class="name">yesterday</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">datetime64</span><span class="punctuation">(</span><span class="literal string single">'today'</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span> <span class="operator">-</span> <span class="name">np</span><span class="operator">.</span><span class="name">timedelta64</span><span class="punctuation">(</span><span class="literal number integer">1</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span>
<span class="name">today</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">datetime64</span><span class="punctuation">(</span><span class="literal string single">'today'</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span>
<span class="name">tomorrow</span> <span class="operator">=</span> <span class="name">np</span><span class="operator">.</span><span class="name">datetime64</span><span class="punctuation">(</span><span class="literal string single">'today'</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span> <span class="operator">+</span> <span class="name">np</span><span class="operator">.</span><span class="name">timedelta64</span><span class="punctuation">(</span><span class="literal number integer">1</span><span class="punctuation">,</span> <span class="literal string single">'D'</span><span class="punctuation">)</span>
</pre>
</li>
<li><p class="first">How to get all the dates corresponding to the month of July 2016? (★★☆)</p>

View File

@@ -278,18 +278,32 @@ Thanks to Michiaki Ariga, there is now a
Z2 = np.random.randint(0,10,10)
print(np.intersect1d(Z1,Z2))
#. How to ignore all numpy warnings (not recommended)? (★☆☆)
.. code-block:: python
# Suicide mode on
defaults = np.seterr(all="ignore")
Z = np.ones(1)/0
# Back to sanity
np.seterr(**defaults)
#. Is the following expressions true? (★☆☆)
.. code-block:: python
np.sqrt(-1) == np.emath.sqrt(-1)
#. How to get the current date ? (★☆☆)
#. How to get the dates of yesterday, today and tomorrow? (★☆☆)
.. code-block:: python
np.datetime64('today', 'D')
np.datetime64('now', 'D')
yesterday = np.datetime64('today', 'D') - np.timedelta64(1, 'D')
today = np.datetime64('today', 'D')
tomorrow = np.datetime64('today', 'D') + np.timedelta64(1, 'D')
#. How to get all the dates corresponding to the month of July 2016? (★★☆)