擅长:python、mysql、java
<p>默认情况下,标准排序将考虑所包含列表的其他列。在</p>
<p>因此,只使用不带任何键的普通排序函数。在</p>
<pre><code>ls = [[100,50],[100,49],[100,64]]
ls.sort()
# ls is sorted w.r.t. all "columns": [[100, 49], [100, 50], [100, 64]]
</code></pre>
<p>还可以看看<a href="https://docs.python.org/2/library/stdtypes.html#sequence-types-str-unicode-list-tuple-bytearray-buffer-xrange" rel="nofollow">documentation</a>[emphasis mine]:</p>
<blockquote>
<p>Sequence types also support comparisons. <strong>In particular, tuples and lists are compared lexicographically by comparing corresponding elements.</strong> This means that to compare equal, every element must compare equal and the two sequences must be of the same type and have the same length. (For full details see <a href="https://docs.python.org/2/reference/expressions.html#comparisons" rel="nofollow">Comparisons</a> in the language reference.)</p>
</blockquote>
<p>但是,如果需要选择特定的列来定义排序顺序,我建议使用<a href="https://docs.python.org/2/library/operator.html#operator.itemgetter" rel="nofollow">^{<cd1>}</a>作为<code>key</code>函数。在</p>