# How to combine mesh from Exodus2 file with data from CSV file

**URL:** https://discourse.paraview.org/t/how-to-combine-mesh-from-exodus2-file-with-data-from-csv-file/7533
**Category:** Development
**Tags:** exodus
**Created:** [July 1, 2021, 1:12pm UTC](https://discourse.paraview.org/t/how-to-combine-mesh-from-exodus2-file-with-data-from-csv-file/7533 "2021-07-01T13:12:39Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![jherb](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/j/e19adc/32.png) [@jherb](https://discourse.paraview.org/u/jherb)
#### Post date: [July 1, 2021, 1:12pm UTC](https://discourse.paraview.org/t/how-to-combine-mesh-from-exodus2-file-with-data-from-csv-file/7533/1 "2021-07-01T13:12:39Z")

</div>

I have the following use case:

I would like to load the mesh from an Exodus2 file and combine it with data from a CSV file. The Exdous2 mesh contains cell regions recognized by the normal Exodus reader as blocks. Now the CSV file contains for different timesteps the values of a variable for each of the blocks.

```auto
# time,block1,block2,...
0,1,2,...
1,1,2,...
2,2,3,...
...

```

The value of a block/region given in the CSV file should be assigned to all cells within the corresponding block.

How would I approach this problem? Write a new reader? A programmable source/filter?

I have found [this](https://discourse.paraview.org/t/transform-exodus-data-with-programmable-filter/4107) but how to do it for multiple time steps.

If implementing a new reader: Which of the existing readers could be an example? Do I have to/can I inherite from the existing Exodus reader?

Sorry, if this is already solved by some existing solution, but I have only found pieces of what I would like to do.