# How to extract data form PlotDataOverTime filer with python/pvpython

**URL:** https://discourse.paraview.org/t/how-to-extract-data-form-plotdataovertime-filer-with-python-pvpython/17456
**Category:** ParaView Support
**Tags:** python
**Created:** [February 27, 2026, 11:04am UTC](https://discourse.paraview.org/t/how-to-extract-data-form-plotdataovertime-filer-with-python-pvpython/17456 "2026-02-27T11:04:12Z")
**Posts on this page:** 2
**Page:** 1

<div class="post-metadata">

### Author: ![DioCanada](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/d/3da27b/32.png) [@DioCanada](https://discourse.paraview.org/u/DioCanada)
#### Post date: [February 27, 2026, 11:04am UTC](https://discourse.paraview.org/t/how-to-extract-data-form-plotdataovertime-filer-with-python-pvpython/17456/1 "2026-02-27T11:04:13Z")

</div>

Hello all,

I’m writing a pvpython script to evaluate the mean flow over a surface for every time step, and do some further calculation with the extracted data.

As a first approach, i applied the integrate variables filter (iv) and used a for loop to cycle over times steps in order to extract the data using the servermanager.Fetch(iv) method.  
Here a summary of what I do, just to get an idea.

```auto
iv= IntegrateVariables(Input=sda) # sda is the surface
iv.UpdatePipeline()
iv_data= servermanager.Fetch(iv)

for t in timesteps:
  iv.UpdatePipeline(time=t) # update pipline at t
  data_iv = servermanager.Fetch(iv)

  flow_temp = data_iv .GetRowData().GetArray("velocity")
  flow_data[surf_id] = vnp.vtk_to_numpy(flow_temp )

```

However, fetching data every time is not the smarter way, I think.  
Thus, I figured out I can use the PlotDataOverTime filter to avoid this.  
However, i cannot find a way to access to the “Row Data” of the filter.

Can you explain me how to do this?

Here a small part of my code to attempt on figuring what type of attributes the `PlotDataOverTime` filter had:

```auto
dataotime = PlotDataOverTime(Input=iv)
pdataotime.UpdatePipeline()
data_pdataotime = servermanager.Fetch(pdataotime)
print(“RowData plot over time:”, data_pdataotime.GetData.keys())

```

I know that I can export the data to a csv and then read the csv inside the script, but for me does not make sense that i cannot acces to the data directly using the `PlotDataOverTime` object itself.

Moreover, I found that using  
`PlotDataOverTime(Input=sda)`  
directly on the surface provides sometimes similar results with respect to

```auto
iv= IntegrateVariables(Input=sda) # sda is the surface
iv.UpdatePipeline()
PlotDataOverTime(Input=iv)

```

Why? Is it because `PlotDataOverTime` evaluate the average over the surface?

Thanks in advance, any help would be highly appreciated.  
Cheers!

---

<div class="post-metadata">

### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [March 2, 2026, 9:22am UTC](https://discourse.paraview.org/t/how-to-extract-data-form-plotdataovertime-filer-with-python-pvpython/17456/2 "2026-03-02T09:22:00Z")

</div>

> [@DioCanada](#):
>
> pvpython script to evaluate the mean flow over a surface for every time step, and do some further calculation with the extracted data.

Do not do that, instead write a programmable filter that will do the processing on the server side.