擅长:python、mysql、java
<blockquote>
<pre><code>I guess string 'NAN' does not mean Non-Value Nan, you already got the solution, you can check my code too
</code></pre>
</blockquote>
<pre><code>df = df[df.ne('NAN')].bfill()
Criteria Col1 Col2 Col3
0 Jan10Sales 12 13 4
1 Feb10Sales 1 3 4
2 Mar10Sales 5 13 14
3 Apr10Sales 5 18 12
4 May10Sales 6 18 19
</code></pre>