擅长:python、mysql、java
<p>你有一个正确的开始</p>
<pre class="lang-py prettyprint-override"><code>for key, val in dataframes.items():
*_, date = key.split("_")
val["Date"] = pd.date_range(start=date, end=date, periods=len(val))
</code></pre>
<p>如果要更改日期格式,可以这样做</p>
<pre class="lang-py prettyprint-override"><code>for key, val in dataframes.items():
*_, date = key.split("_")
val["Date"] = pd.date_range(start=date, end=date, periods=len(val)).strftime('%m/%d/%Y') #<==== here
</code></pre>
<p>以及<a href="https://docs.python.org/3/library/datetime.html#strftime-and-strptime-behavior" rel="nofollow noreferrer">documentation about date format</a></p>
<h2>编辑:</h2>
<p>前面提到的awnser过于复杂,因为当您在新的列赋值中传递单个值时,pandas将自动填充整个列</p>
<p>见@jezrael awser</p>
<p>要使用@jezrael awser更改日期格式,只需添加<code>format='%m/%d/%Y'</code></p>
<pre class="lang-py prettyprint-override"><code>for key, val in dataframes.items():
dataframes[key]['Key'] = pd.to_datetime(key.split('_')[1], format='%m/%d/%Y')
</code></pre>