# Topography.Output to file

**URL:** <https://community.geodynamics.org/t/topography-output-to-file/4006>\
**Category:** ASPECT\
**Created:** [March 20, 2025, 2:25am UTC](https://community.geodynamics.org/t/topography-output-to-file/4006 "2025-03-20T02:25:23Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![vladycm](https://avatars.discourse-cdn.com/v4/letter/v/b5a626/32.png) [@vladycm](https://community.geodynamics.org/u/vladycm)\
**Post date:** [March 20, 2025, 2:25am UTC](https://community.geodynamics.org/t/topography-output-to-file/4006/1 "2025-03-20T02:25:23Z")

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Hi.

I noticed that in ASPECT 3.0.0 there is this option: “_If ’Topography.Output to file’ is set to true, also outputs topography into text files named topography.NNNNN’ in the output directory, where NNNNN is the number of the time step._” I am not sure how to use it. I tried as:  
set Topography.Output to file = true but got errors, it is not recognized.

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**Author:** ![bangerth](https://yyz2.discourse-cdn.com/flex036/user_avatar/community.geodynamics.org/bangerth/32/52_2.png) [@bangerth](https://community.geodynamics.org/u/bangerth)\
**Post date:** [March 20, 2025, 3:06am UTC](https://community.geodynamics.org/t/topography-output-to-file/4006/2 "2025-03-20T03:06:53Z")

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> [@vladycm](#):
>
> Topography.Output to file

This is meant to say “In subsection `Topography`, the parameter named `Output to file`”. To be precise, the subsection `Topography` is itself within subsection `Postprocess`.

For future reference, let me also point you to this page: [https://aspect.geodynamics.org/doc/parameter\_view/parameters.xml](https://aspect.geodynamics.org/doc/parameter_view/parameters.xml) There, you can search for individual parameters, which might have led you to subsection `Topography` and also to the parameter in question.

Best  
W.

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**Author:** ![jbnaliboff](https://avatars.discourse-cdn.com/v4/letter/j/58956e/32.png) [@jbnaliboff](https://community.geodynamics.org/u/jbnaliboff)\
**Post date:** [March 20, 2025, 3:15am UTC](https://community.geodynamics.org/t/topography-output-to-file/4006/3 "2025-03-20T03:15:58Z")

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Hi Vlad,

Thank you for posting this question to the forum, and fortunately there is a straightforward solution.

The parameter name is in fact `Output to file` ([documentation](https://aspect-documentation.readthedocs.io/en/latest/parameters/Postprocess.html#parameters-postprocess-topography-output-20to-20file)).

What you posted above is parameter name as described in the topography postprocessor documentation, which labeled the parameter `Topography.Output to file`. I’ve proposed a revised description [here](https://github.com/geodynamics/aspect/pull/6260).

Please let us know if your models work with the updated parameter name and thank you for helping to identify an area where we potentially improve the documentation.

Cheers,  
John

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**Author:** ![jbnaliboff](https://avatars.discourse-cdn.com/v4/letter/j/58956e/32.png) [@jbnaliboff](https://community.geodynamics.org/u/jbnaliboff)\
**Post date:** [March 20, 2025, 3:26am UTC](https://community.geodynamics.org/t/topography-output-to-file/4006/4 "2025-03-20T03:26:41Z")

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Oops, I see @bangerth beat me to it and also posted a PR 🙂

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**Author:** ![vladycm](https://avatars.discourse-cdn.com/v4/letter/v/b5a626/32.png) [@vladycm](https://community.geodynamics.org/u/vladycm)\
**Post date:** [March 20, 2025, 4:41am UTC](https://community.geodynamics.org/t/topography-output-to-file/4006/5 "2025-03-20T04:41:44Z")

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Hi Bangerth and John,

Great, thanks for the tip. It worked well.

Best.  
Vlad