擅长:python、mysql、java
<p>使用:<a href="https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.ffill.html" rel="nofollow noreferrer">^{<cd1>}</a>。在这里您可以了解如何使用<strong>就地<strong>:<a href="https://stackoverflow.com/questions/43893457/python-pandas-understanding-inplace-true">^{<cd2>}</a></p>
<pre><code>#df.replace('Nan',np.nan) #if NaN is string
cols=['Fruits','Veg','Non_veg']
df[cols]=df[cols].ffill()
</code></pre>