# Pin Cell: Settings Object

**URL:** <https://openmc.discourse.group/t/pin-cell-settings-object/1286>\
**Category:** User Support\
**Created:** [June 29, 2021, 10:56pm UTC](https://openmc.discourse.group/t/pin-cell-settings-object/1286 "2021-06-29T22:56:46Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![LukeLabrie](https://avatars.discourse-cdn.com/v4/letter/l/c37758/32.png) [@LukeLabrie](https://openmc.discourse.group/u/LukeLabrie)\
**Post date:** [June 29, 2021, 10:56pm UTC](https://openmc.discourse.group/t/pin-cell-settings-object/1286/1 "2021-06-29T22:56:46Z")

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Hi all,

I am new to nuclear modeling in general and I’m working through the pin cell example and I have a question regarding the below section of code:

```auto
settings = openmc.Settings()
settings.source = source
settings.batches = 100
settings.inactive = 10
settings.particles = 1000

```

I interpret this to mean that our source of neutrons is “source”, and that there will be 100 batches of 1000 particles starting from this source. 10 out of these 100 batches will be inactive. Correct so far? And why have inactive batches?

Appreciate any guidance here.

Thanks,  
Luke

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<div class="post-metadata">

**Author:** ![mkreher13](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/mkreher13/32/4093_2.png) [@mkreher13](https://openmc.discourse.group/u/mkreher13)\
**Post date:** [July 1, 2021, 8:22pm UTC](https://openmc.discourse.group/t/pin-cell-settings-object/1286/2 "2021-07-01T20:22:53Z")

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Hello Luke. You are right about all that! The point of having inactive batches is to allow the initial source “guess” to converge to the correct source before you start tallying results. It is explained here in section 7.2.2. [7. Execution Settings — OpenMC Documentation](https://docs.openmc.org/en/stable/usersguide/settings.html#generation-of-output-files)

Best,  
Miriam