# How to downsample the dipole points of a distributed source？

**URL:** <https://mne.discourse.group/t/how-to-downsample-the-dipole-points-of-a-distributed-source/3275>\
**Category:** Support & Discussions\
**Created:** [June 18, 2021, 6:40am UTC](https://mne.discourse.group/t/how-to-downsample-the-dipole-points-of-a-distributed-source/3275 "2021-06-18T06:40:35Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Xiaofang](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/xiaofang/32/265_2.png) [@Xiaofang](https://mne.discourse.group/u/Xiaofang)\
**Post date:** [June 18, 2021, 6:40am UTC](https://mne.discourse.group/t/how-to-downsample-the-dipole-points-of-a-distributed-source/3275/1 "2021-06-18T06:40:36Z")

</div>

Maybe there is a way to downsample the source dipole points?  
I chose the frontal lobe as the area I am interested in, but there are 48,146 source dipole points in it. I don’t need that many, 2000 is enough.  
So is there any way to downsample Label instances?  
Or down-sampling the entire source space is also possible.

---

<div class="post-metadata">

**Author:** ![drammock](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/drammock/32/4_2.png) [@drammock](https://mne.discourse.group/u/drammock)\
**Post date:** [June 29, 2021, 3:09pm UTC](https://mne.discourse.group/t/how-to-downsample-the-dipole-points-of-a-distributed-source/3275/2 "2021-06-29T15:09:21Z")

</div>

[mne.setup\_source\_space()](https://mne.tools/stable/generated/mne.setup_source_space.html#mne.setup_source_space) lets you choose the vertex spacing (`ico5`, `oct6`, etc). If you’re working with a label that has high vertex density and a source space with lower density, then you can use [Label.restrict()](https://mne.tools/stable/generated/mne.Label.html#mne.Label.restrict).

---

<div class="post-metadata">

**Author:** ![Xiaofang](https://yyz2.discourse-cdn.com/free1/user_avatar/mne.discourse.group/xiaofang/32/265_2.png) [@Xiaofang](https://mne.discourse.group/u/Xiaofang)\
**Post date:** [June 30, 2021, 2:23am UTC](https://mne.discourse.group/t/how-to-downsample-the-dipole-points-of-a-distributed-source/3275/3 "2021-06-30T02:23:22Z")

</div>

I get the src instance by reading the .fif format file, so I can no longer modify the src.  
I did not find a function for downsampling in the [SourceSpace](https://mne.tools/stable/generated/mne.SourceSpaces.html?highlight=sourcespace) class, so I can’t downsample the Label through the [Label.restrict()](https://mne.tools/stable/generated/mne.Label.html#mne.Label.restrict) method.