# Outputting Stress at Vertices

**URL:** <https://community.geodynamics.org/t/outputting-stress-at-vertices/1662>\
**Category:** PyLith\
**Created:** [January 27, 2021, 8:10pm UTC](https://community.geodynamics.org/t/outputting-stress-at-vertices/1662 "2021-01-27T20:10:11Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![kimtaeho07](https://yyz2.discourse-cdn.com/flex036/user_avatar/community.geodynamics.org/kimtaeho07/32/449_2.png) [@kimtaeho07](https://community.geodynamics.org/u/kimtaeho07)\
**Post date:** [January 27, 2021, 8:10pm UTC](https://community.geodynamics.org/t/outputting-stress-at-vertices/1662/1 "2021-01-27T20:10:11Z")

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Is outputting stress at vertices possible in Pylith? It seems that outputting at vertices is only possible for displacement and velocity.

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**Author:** ![baagaard](https://yyz2.discourse-cdn.com/flex036/user_avatar/community.geodynamics.org/baagaard/32/615_2.png) [@baagaard](https://community.geodynamics.org/u/baagaard)\
**Post date:** [January 27, 2021, 8:30pm UTC](https://community.geodynamics.org/t/outputting-stress-at-vertices/1662/2 "2021-01-27T20:30:48Z")

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In PyLith v2.2 stress is only available at the numerical quadrature points within a cell. Most visualization tools only understand a single point within a cell (they don’t know the locations of the numerical quadrature points), so we typically use the average, which is available via `pylith.meshio.CellFilterAvg`. See the examples and manual for details.

In the next PyLith release, it will be possible to project fields into a desire basis (for example, basis order 0 = cells, basis order 1 = vertices). Note that the field is only as accurate as the original discretization. We will try to explain this clearly in the manual.

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**Author:** ![kimtaeho07](https://yyz2.discourse-cdn.com/flex036/user_avatar/community.geodynamics.org/kimtaeho07/32/449_2.png) [@kimtaeho07](https://community.geodynamics.org/u/kimtaeho07)\
**Post date:** [January 27, 2021, 8:33pm UTC](https://community.geodynamics.org/t/outputting-stress-at-vertices/1662/3 "2021-01-27T20:33:52Z")

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I see, thank you very much for your help.