# DAGMC Geometry not on origin

**URL:** <https://openmc.discourse.group/t/dagmc-geometry-not-on-origin/4791>\
**Category:** User Support\
**Created:** [September 12, 2024, 8:34pm UTC](https://openmc.discourse.group/t/dagmc-geometry-not-on-origin/4791 "2024-09-12T20:34:50Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![thallam](https://avatars.discourse-cdn.com/v4/letter/t/71c47a/32.png) [@thallam](https://openmc.discourse.group/u/thallam)\
**Post date:** [September 12, 2024, 8:34pm UTC](https://openmc.discourse.group/t/dagmc-geometry-not-on-origin/4791/1 "2024-09-12T20:34:50Z")

</div>

Hello, I am using DAGMC to simulate a reactor with a point source at (0,0,0). however when i plot my geometry the faces that should be on the origin planes are off by very small margins. Here is my plotting code and the 1 plot output of the center one. The first one shows nothing and the third one shows more of that geometry. The geometry is flat on the y plane in my CAD software before using CAD\_to\_OpenMC to create a mesh and an h5m file to import into OpenMC. Any reason why this is happening?

plot = openmc.Plot()  
plot.basis = ‘xz’  
plot.origin = (0, -1e-13, 0)  
plot.width = (0.6, 0.6)  
plot.pixels = (400, 400)  
openmc.plot\_inline(plot)

```
plot = openmc.Plot()
plot.basis = 'xz'
plot.origin = (0, -1e-15, 0)
plot.width = (0.6, 0.6)
plot.pixels = (400, 400)
openmc.plot_inline(plot)

plot = openmc.Plot()
plot.basis = 'xz'
plot.origin = (0, -1e-17, 0)
plot.width = (0.6, 0.6)
plot.pixels = (400, 400)
openmc.plot_inline(plot)

```

![plot_32](https://global.discourse-cdn.com/free1/uploads/openmc/original/2X/3/3260bd71512d90458fb77ac75777186e240c7a68.png)