> For the complete documentation index, see [llms.txt](https://docs.ladybug.tools/ladybug-primer/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ladybug.tools/ladybug-primer/components/4_extra/filter_by_normal.md).

# Filter by Normal

![](/files/OkrZyLulDKtBaFXwQh4W)

![](/files/EodhR0TtaSFLClTwHjx8) - [\[source code\]](https://github.com/ladybug-tools/ladybug-grasshopper/blob/master/ladybug_grasshopper/src//LB%20Filter%20by%20Normal.py)

Filter or select faces of geometry based on their orientation.

### Inputs

* **north**

A number between -360 and 360 for the counterclockwise difference between the North and the positive Y-axis in degrees. 90 is West and 270 is East. This can also be Vector for the direction to North. (Default: 0)

* **geometry \[Required]**

Rhino Breps and/or Rhino Meshes which will be broken down into individual planar faces and filtered based on the direction they face.

* **orientation \[Required]**

Text for the direction that the geometry is facing. This can also be a number between 0 and 360 for the azimuth (clockwise horizontal degrees from North) that the geometry should face. Choose from the following:

```
* N = North

* NE = Northeast

* E = East

* SE = Southeast

* S = South

* SW = Southwest

* W = West

* NW = Northwest

* Up = Upwards

* Down = Downwards
```

* **up\_angle**

A number in degrees for the maximum declination angle from the positive Z Axis that is considerd up. This should be between 0 and 90 for the results to be practical. (Default: 30).

* **down\_angle**

A number in degrees for the maximum angle difference from the newative Z Axis that is considerd down. This should be between 0 and 90 for the results to be practical. (Default: 30).

* **horiz\_angle**

Angle in degrees for the horizontal deviation from \_orientation that is still considered to face that orientation. This should be between 0 and 90 for the results to be practical. Note that this input has no effect when the input orientation is "Up" or "Down". (Default: 23).

### Outputs

* **report**

...

* **sel\_geo**

Selected faces of the input geometry that are facing the direction corresponding to the input criteria.


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