# Group lines which have the same start point

**URL:** <https://forum.dynamobim.com/t/group-lines-which-have-the-same-start-point/7696>\
**Category:** Lists-Logic\
**Created:** [November 23, 2016, 4:49am UTC](https://forum.dynamobim.com/t/group-lines-which-have-the-same-start-point/7696 "2016-11-23T04:49:46Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![yeuthantoc](https://avatars.discourse-cdn.com/v4/letter/y/9f8e36/32.png) [@yeuthantoc](https://forum.dynamobim.com/u/yeuthantoc)\
**Post date:** [November 23, 2016, 4:49am UTC](https://forum.dynamobim.com/t/group-lines-which-have-the-same-start-point/7696/1 "2016-11-23T04:49:46Z")

</div>

Hi all,  
As the title, I have a list of lines was flattened like this:

 ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/6/7/67e7cecc2724dff9807ec30827d383a440f0c360.png)

And I want it to be look like:

 ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/f/d/fd66a3647b803ba1d4860411996fc1bea013a7bb.png)

I mean it will be group the lines which have same start point at **X point** to sub lists  
Please show me how to do it

Thank you!  
Hoang Lynh

---

<div class="post-metadata">

**Author:** ![Alisder\_Brown](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/alisder_brown/32/14995_2.png) [@Alisder\_Brown](https://forum.dynamobim.com/u/Alisder_Brown)\
**Post date:** [November 23, 2016, 9:34am UTC](https://forum.dynamobim.com/t/group-lines-which-have-the-same-start-point/7696/2 "2016-11-23T09:34:09Z")

</div>

You should be able to just feed your flattened list of start points into a “List.GroupByKey” node (Flattened list into both inputs) an this will group them for you

---

<div class="post-metadata">

**Author:** ![jostein\_olsen](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/jostein_olsen/32/8570_2.png) [@jostein\_olsen](https://forum.dynamobim.com/u/jostein_olsen)\
**Post date:** [November 23, 2016, 10:25am UTC](https://forum.dynamobim.com/t/group-lines-which-have-the-same-start-point/7696/3 "2016-11-23T10:25:30Z")

</div>

Or GroupByFunction works as well.

 ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/5/a/5a411c2cce53b3e1abfd5194a34864265925e0c7.png)

---

<div class="post-metadata">

**Author:** ![yeuthantoc](https://avatars.discourse-cdn.com/v4/letter/y/9f8e36/32.png) [@yeuthantoc](https://forum.dynamobim.com/u/yeuthantoc)\
**Post date:** [November 24, 2016, 2:39am UTC](https://forum.dynamobim.com/t/group-lines-which-have-the-same-start-point/7696/4 "2016-11-24T02:39:08Z")

</div>

Thanks all, it worked perfect!