擅长:python、mysql、java
<blockquote>
<p>I am able to get for an array but unable to find for DataFrame</p>
</blockquote>
<p>可以展平数据帧以使用在1D数组上操作的函数。所以如果你同意的话(可能比EdChum的回答慢):</p>
<pre><code>>>> import pandas as pd
>>> df = pd.DataFrame({'a': [-3, -2, 4], 'b': [-2, 2, 5], 'c': [-1, 3, 7], 'd': [1, 4, 8]})
>>> df.values
array([[-3, -2, -1, 1],
[-2, 2, 3, 4],
[ 4, 5, 7, 8]])
>>> df.values.flatten()
array([-3, -2, -1, 1, -2, 2, 3, 4, 4, 5, 7, 8])
>>> sum(n < 0 for n in df.values.flatten())
4
</code></pre>