# Detecting and navigating in a matrix

**URL:** <https://forums.openmv.io/t/detecting-and-navigating-in-a-matrix/1887>\
**Category:** OpenMV Boards\
**Created:** [August 18, 2020, 6:55pm UTC](https://forums.openmv.io/t/detecting-and-navigating-in-a-matrix/1887 "2020-08-18T18:55:26Z")\
**Posts on this page:** 1\
**Showing post:** 13

<div class="post-metadata">

**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\
**Post date:** [August 24, 2020, 7:15pm UTC](https://forums.openmv.io/t/detecting-and-navigating-in-a-matrix/1887/13 "2020-08-24T19:15:12Z")

</div>

Robust is not stable for a pure horizontal line…

Must be something here loosing precision.

[https://github.com/openmv/openmv/blob/master/src/omv/img/stats.c#L1070](https://github.com/openmv/openmv/blob/master/src/omv/img/stats.c#L1070)

…

I think it’s something to do with the atan2 as x gets close close to zero.  
[regular.mp4](https://forums.openmv.io/uploads/short-url/nBedVWktgyUqaV9oEHciOWrprXy.mp4) (85.6 KB)  
[robust.mp4](https://forums.openmv.io/uploads/short-url/gGNVQqWIBRgyGzPdEvsXIJ5iJRr.mp4) (63.7 KB)

---

_[View the full topic](https://forums.openmv.io/t/detecting-and-navigating-in-a-matrix/1887)._