Example in Lisbon

> **Next**: Create an example for Lisbon! @partavogen already [forked](https://github.com/partavogen/od2net) this repo and is trying to make that, but also facing some issues.

_Originally posted by @temospena in https://github.com/Urban-Analytics-Technology-Platform/od2net/issues/2#issuecomment-1866726352_

Hi all,

We are exploring od2net in Lisbon, and facing some problems.
Regarding #18 , how can we add this as the gradient value? Is it a matter to put the geotiff in a folder and point to it, or we need to pre-process with the data?
Here is a nice geotiff of Lisbon area: https://github.com/U-Shift/Declives-RedeViaria/blob/main/raster/LisboaIST_clip_r1.tif (10m res)
https://github.com/U-Shift/Declives-RedeViaria/blob/main/raster/LisboaCOPERNICUS_clip.tif (25m res)

Thanks!