擅长:python、mysql、java
<p>阿兰格函数的帮助说</p>
<pre><code> For floating point arguments, the length of the result is
``ceil((stop - start)/step)``. Because of floating point overflow,
this rule may result in the last element of `out` being greater
than `stop`.
</code></pre>
<p>对于Python2.7,浮点数字和字符串之间的转换现在在大多数平台上都是正确的四舍五入的。</p>
<p>在2.7中</p>
<pre><code>>>> float(repr(2.3))
2.3
</code></pre>
<p>在2.6中</p>
<pre><code>>>> float(repr(2.3))
2.2999999999999998
</code></pre>