擅长:python、mysql、java
<p><strong>简短回答:使用<code>tremor_0['X']</code>。你知道吗</p>
<p><strong>长答案</strong></p>
<p>首先,<code>tremor_0[['X']]</code>和<code>tremor_0['X']</code>是不一样的。你知道吗</p>
<p>假设您有一个数据帧:</p>
<pre><code>df = pd.DataFrame(np.ndarray((100, 10)), columns=['x_%i' % i for i in range(10)])
type(df[['x_0']])
# pandas.core.frame.DataFrame
type(df['x_0'])
# pandas.core.series.Series
</code></pre>
<p>更重要的是,它们的形状不同</p>
<pre><code>df[['x_0']].shape
# (100, 1)
df['x_0'].shape
# (100, )
</code></pre>
<p>因为它对<code>axis=-1</code>应用过滤器,所以<code>scipy.signal.lfilter</code>的处理方式不同。你知道吗</p>
<blockquote>
<p><strong>axis : int, optional</strong>
The axis of the input data array along which to apply the linear filter. The filter is applied to each subarray along this axis. Default is -1.</p>
</blockquote>
<p>如果将<code>lfilter</code>参数更改为<code>axis = 0</code>,则<code>butter_bandpass_filter</code>返回带有示例值的数组。但请记住,生成的数组将遵循输入的形状。你知道吗</p>