QST: Pandas Dataframe Rolling based on timeframe throwing exception “window must be an integer”
This is the schema of the dataframe i'm using to evaluate aggregate based on rolling timeframe.

```
AssetId int64 
TimeStampCol datetime64[ns]
paramName1 object
paramName2 object 
paramName3 object
```
My requirement is that I want to find the min of paramName1 over the period of past 1 hour data.

I'm forming the eval expression dynamically which will be like 

`streamingDf.rolling('1H').paramName1.min()`

```eval(f'streamingDf.rolling('1H').paramName1.min()') ```

then I'm evaluating the expression to get the result dataframe.

Pandas Dataframe ***rolling based on timeframe*** throwing exception

`window must be an integer`

I'm also explicitly setting a datetime column as the index of this dataframe, before evaluating this expression.

```
streamingDf['TimeStampCol'] = pd.to_datetime(streamingDf['TimeStampCol'])
streamingDf.set_index('TimeStampCol')
```

Can someone help to resolve this issue.



- [ ] I have searched the [[pandas] tag](https://stackoverflow.com/questions/tagged/pandas) on StackOverflow for similar questions.

- [ ] I have asked my usage related question on [StackOverflow](https://stackoverflow.com).

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