kennethreitz/dive-into-python3
1
0
Fork 0
mirror of https://github.com/kennethreitz/dive-into-python3.git synced 2026-06-05 15:00:18 +00:00
Code Issues Packages Projects Releases Wiki Activity

skeleton of new native-datatype#sets section

Browse Source
This commit is contained in:
Mark Pilgrim
2009-07-03 23:01:59 -04:00
parent 4919d9fd61
commit fbd3c859de
3 changed files with 207 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files
native-datatypes.html
+202 -13
View File
@@ -441,25 +441,214 @@ IndexError: pop from empty list</samp></pre>
<p class=a>&#x2042;
<h2 id=sets>Sets</h2>
<p>FIXME
<!--
{values} and set()
<pre class=screen>
<a><samp class=p>>>> </samp><kbd class=pp>a_set = {1}</kbd> <span class=u>&#x2460;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>type(a_set)</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>&lt;class 'set'></samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set = {1, 2}</kbd> <span class=u>&#x2462;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2}</samp></pre>
<ol>
<li>FIXME
<li>
<li>
</ol>
add() and +
in
discard() and remove() and pop()
<p>You can create a set out of a <a href=#lists>list</a>.
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_list = ['a', 'b', 'mpilgrim', True, False, 42]</kbd>
<a><samp class=p>>>> </samp><kbd class=pp>a_set = set(a_list)</kbd> <span class=u>&#x2460;</span></a>
<a><samp class=p>>>> </samp><kbd class=pp>a_set</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>{'a', False, 'b', True, 'mpilgrim', 42}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_list</kbd> <span class=u>&#x2462;</span></a>
<samp class=pp>['a', 'b', 'mpilgrim', True, False, 42]</samp></pre>
<ol>
<li>FIXME
<li>
<li>
</ol>
union()
intersection()
difference()
symmetric_difference()
<p>You can create an empty set.
issubset()
issuperset()
isdisjoint()
-->
<pre class=screen>
<a><samp class=p>>>> </samp><kbd class=pp>a_set = set()</kbd> <span class=u>&#x2460;</span></a>
<a><samp class=p>>>> </samp><kbd class=pp>a_set</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>set()</samp>
<a><samp class=p>>>> </samp><kbd class=pp>type(a_set)</kbd> <span class=u>&#x2462;</span></a>
<samp class=pp>&lt;class 'set'></samp>
<a><samp class=p>>>> </samp><kbd class=pp>len(a_set)</kbd> <span class=u>&#x2463;</span></a>
<samp class=pp>0</samp>
<a><samp class=p>>>> </samp><kbd class=pp>not_sure = {}</kbd> <span class=u>&#x2464;</span></a>
<a><samp class=p>>>> </samp><kbd class=pp>type(not_sure)</kbd> <span class=u>&#x2465;</span></a>
<samp class=pp>&lt;class 'dict'></samp></pre>
<ol>
<li>FIXME
<li>
<li>
<li>
<li>
<li>
</ol>
<h3 id=modifying-sets>Modifying A Set</h3>
<p>FIXME
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_set = {1, 2}</kbd>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.add(3)</kbd> <span class=u>&#x2460;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2, 3}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>len(a_set)</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>3</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.add(1)</kbd> <span class=u>&#x2462;</span></a>
<samp class=pp>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2, 3}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>len(a_set)</kbd> <span class=u>&#x2463;</span></a>
<samp class=pp>3</samp></pre>
<ol>
<li>FIXME
<li>
<li>
<li>
</ol>
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_set = {1, 2, 3}</kbd>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2, 3}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.update({2, 4, 6})</kbd> <span class=u>&#x2460;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2, 3, 4, 6}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.update({3, 6, 9}, {1, 2, 3, 5, 8, 13})</kbd> <span class=u>&#x2461;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2, 3, 4, 5, 6, 8, 9, 13}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.update([10, 20, 30])</kbd> <span class=u>&#x2462;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 2, 3, 4, 5, 6, 8, 9, 10, 13, 20, 30}</samp></pre>
<ol>
<li>FIXME
<li>
<li>
</ol>
<h3 id=removing-from-sets>Removing Items From A Set</h3>
<p>FIXME
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_set = {1, 3, 6, 10, 15, 21, 28, 36, 45}</kbd>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 3, 36, 6, 10, 45, 15, 21, 28}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.discard(10)</kbd> <span class=u>&#x2460;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 3, 36, 6, 45, 15, 21, 28}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.discard(10)</kbd> <span class=u>&#x2461;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 3, 36, 6, 45, 15, 21, 28}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.remove(21)</kbd> <span class=u>&#x2462;</span></a>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{1, 3, 36, 6, 45, 15, 28}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.remove(21)</kbd> <span class=u>&#x2463;</span></a>
<samp class=pp>Traceback (most recent call last):
File "&lt;stdin>", line 1, in &lt;module>
KeyError: 21</samp></pre>
<ol>
<li>FIXME
<li>
<li>
<li>
</ol>
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_set = {1, 3, 6, 10, 15, 21, 28, 36, 45}</kbd>
<samp class=p>>>> </samp><kbd class=pp>a_set.pop()</kbd>
<samp class=pp>1</samp>
<samp class=p>>>> </samp><kbd class=pp>a_set.pop()</kbd>
<samp class=pp>3</samp>
<samp class=p>>>> </samp><kbd class=pp>a_set.pop()</kbd>
<samp class=pp>36</samp>
<samp class=p>>>> </samp><kbd class=pp>a_set</kbd>
<samp class=pp>{6, 10, 45, 15, 21, 28}</samp></pre>
<ol>
<li>FIXME
</ol>
<h3 id=common-set-operations>Common Set Operations</h3>
<p>FIXME
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_set = {2, 4, 5, 9, 12, 21, 30, 51, 76, 127, 195}</kbd>
<a><samp class=p>>>> </samp><kbd class=pp>30 in a_set</kbd> <span class=u>&#x2460;</span></a>
<samp class=pp>True</samp>
<a><samp class=p>>>> </samp><kbd class=pp>31 in a_set</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>False</samp>
<samp class=p>>>> </samp><kbd class=pp>b_set = {1, 2, 3, 5, 6, 8, 9, 12, 15, 17, 18, 21}</kbd>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.union(b_set)</kbd> <span class=u>&#x2462;</span></a>
<samp class=pp>{1, 2, 195, 4, 5, 6, 8, 12, 76, 15, 17, 18, 3, 21, 30, 51, 9, 127}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.intersection(b_set)</kbd> <span class=u>&#x2463;</span></a>
<samp class=pp>{9, 2, 12, 5, 21}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.difference(b_set)</kbd> <span class=u>&#x2464;</span></a>
<samp class=pp>{195, 4, 76, 51, 30, 127}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.symmetric_difference(b_set)</kbd> <span class=u>&#x2465;</span></a>
<samp class=pp>{1, 3, 4, 6, 8, 76, 15, 17, 18, 195, 127, 30, 51}</samp></pre>
<ol>
<li>FIXME
<li>
<li>
<li>
<li>
<li>
</ol>
<p>FIXME
<pre class=screen>
# continued from the previous example
<a><samp class=p>>>> </samp><kbd class=pp>b_set.symmetric_difference(a_set)</kbd> <span class=u>&#x2460;</span></a>
<samp class=pp>{3, 1, 195, 4, 6, 8, 76, 15, 17, 18, 51, 30, 127}</samp>
<a><samp class=p>>>> </samp><kbd class=pp>b_set.symmetric_difference(a_set) == a_set.symmetric_difference(b_set)</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>True</samp>
<a><samp class=p>>>> </samp><kbd class=pp>b_set.union(a_set) == a_set.union(b_set)</kbd> <span class=u>&#x2462;</span></a>
<samp class=pp>True</samp>
<a><samp class=p>>>> </samp><kbd class=pp>b_set.intersection(a_set) == a_set.intersection(b_set)</kbd> <span class=u>&#x2463;</span></a>
<samp class=pp>True</samp>
<a><samp class=p>>>> </samp><kbd class=pp>b_set.difference(a_set) == a_set.difference(b_set)</kbd> <span class=u>&#x2464;</span></a>
<samp class=pp>False</samp></pre>
<ol>
<li>FIXME
<li>
<li>
<li>
<li>
</ol>
<p>FIXME
<pre class=screen>
<samp class=p>>>> </samp><kbd class=pp>a_set = {1, 2, 3}</kbd>
<samp class=p>>>> </samp><kbd class=pp>b_set = {1, 2, 3, 4}</kbd>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.issubset(b_set)</kbd> <span class=u>&#x2460;</span></a>
<samp class=pp>True</samp>
<a><samp class=p>>>> </samp><kbd class=pp>b_set.issuperset(a_set)</kbd> <span class=u>&#x2461;</span></a>
<samp class=pp>True</samp>
<samp class=p>>>> </samp><kbd class=pp>a_set.add(5)</kbd>
<a><samp class=p>>>> </samp><kbd class=pp>a_set.issubset(b_set)</kbd> <span class=u>&#x2462;</span></a>
<samp class=pp>False</samp>
<samp class=p>>>> </samp><kbd class=pp>b_set.issuperset(a_set)</kbd>
<samp class=pp>False</samp></pre>
<ol>
<li>FIXME
<li>
<li>
</ol>
<p class=a>&#x2042;