# Grid for unstructured data in separate file?

**URL:** https://discourse.vtk.org/t/grid-for-unstructured-data-in-separate-file/1031
**Category:** Support
**Created:** [May 27, 2019, 10:53am UTC](https://discourse.vtk.org/t/grid-for-unstructured-data-in-separate-file/1031 "2019-05-27T10:53:47Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![janlv](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/j/7bcc69/32.png) [@janlv](https://discourse.vtk.org/u/janlv)
#### Post date: [May 27, 2019, 10:53am UTC](https://discourse.vtk.org/t/grid-for-unstructured-data-in-separate-file/1031/1 "2019-05-27T10:53:47Z")

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Hi,  
to save disk space when writing time-data on a constant unstructured grid, it would be nice to write grid points and cells once in a separate file and reference this file in the subsequent .vtu files? Is that possible? Or is it possible to write the grid data in a .pvd file where the .vtu files are referenced?

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### Author: ![AntoineMazuyer](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/a/71e660/32.png) [@AntoineMazuyer](https://discourse.vtk.org/u/AntoineMazuyer)
#### Post date: [June 27, 2019, 1:02am UTC](https://discourse.vtk.org/t/grid-for-unstructured-data-in-separate-file/1031/2 "2019-06-27T01:02:29Z")

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I really second this request. @janlv, did you find something ?