# Filter group members by category

**URL:** <https://forum.dynamobim.com/t/filter-group-members-by-category/11208>\
**Category:** Uncategorized\
**Created:** [April 21, 2017, 4:01pm UTC](https://forum.dynamobim.com/t/filter-group-members-by-category/11208 "2017-04-21T16:01:05Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Angi92](https://avatars.discourse-cdn.com/v4/letter/a/a587f6/32.png) [@Angi92](https://forum.dynamobim.com/u/Angi92)\
**Post date:** [April 21, 2017, 4:01pm UTC](https://forum.dynamobim.com/t/filter-group-members-by-category/11208/1 "2017-04-21T16:01:05Z")

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Hi everyone! I’m new as Dynamo user. I am trying to understand in which way I can use Dynamo to create a schedule of elements created in a Revit model. Particularly, I have a model of a Hotel room, made up of two parts. In revit, I have created this two parts of the room as groups, containing different elements (walls, floors, generic models…). Now, I would like to recognize this groups in dynamo, recognize the levels of this group, and all the elements of this group. Finally, I want to filter the found elements in order to obtain only the generic model. Is it possible? Can someone help me?

 ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/2/7/2708c3a6d343e8b263c423bf3b4ab19b2c946a81.png)Thank You in advance!

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**Author:** ![Kulkul](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/kulkul/32/49801_2.png) [@Kulkul](https://forum.dynamobim.com/u/Kulkul)\
**Post date:** [April 21, 2017, 4:17pm UTC](https://forum.dynamobim.com/t/filter-group-members-by-category/11208/2 "2017-04-21T16:17:41Z")

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Hi @Angi92

You need to use “List.GroupByKey” node.

 ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/8/1/815b29872d3ecd2755c8e1dfdd3790696e196e80.png)

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**Author:** ![Angi92](https://avatars.discourse-cdn.com/v4/letter/a/a587f6/32.png) [@Angi92](https://forum.dynamobim.com/u/Angi92)\
**Post date:** [April 26, 2017, 6:37am UTC](https://forum.dynamobim.com/t/filter-group-members-by-category/11208/3 "2017-04-26T06:37:28Z")

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Hi Kulkul, first of all thank you for your reply! I have tried to do what you suggested, but it doesn’t work! I attach the image. Any idea? Thanks!

 ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/5/3/53d9ad80991f83cba5aac62492add827fcd1f7b2.png)

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**Author:** ![Kulkul](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/kulkul/32/49801_2.png) [@Kulkul](https://forum.dynamobim.com/u/Kulkul)\
**Post date:** [April 26, 2017, 2:35pm UTC](https://forum.dynamobim.com/t/filter-group-members-by-category/11208/4 "2017-04-26T14:35:43Z")

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@Angi92 Change Lacing to longest at “List.GroupByKey” node.