擅长:python、mysql、java
<p>对于dict理解,使用<code>sum()</code>来计算嵌套字典值的总和;python2.6或更早版本将使用<code>dict()</code>和生成器表达式:</p>
<pre><code># Python 2.7
{k: sum(float(f) for f in v.itervalues()) for k, v in mydict.iteritems()}
# Python 3.x
{k: sum(map(float, v.values())) for k, v in mydict.items()}
# Python 2.6 and before
dict((k, sum(float(f) for f in v.values())) for k, v in mydict.iteritems())
</code></pre>
<p>您可能希望首先存储浮点值。在</p>
<p>演示:</p>
^{pr2}$