DOC: Can I perform operations on the geocube pixels during rasterization? Count, Mean, etc.

Hi this is my first foray into geocube. Thanks for your work here, clearly a good idea.

I’d like to add an example usage that I believe should be possible, but not just quite getting right.

Is it possible to count the number of polygons in a cell, or perform operations on the geocube pixels during rasterization? Imagine a geopandas dataframe with many polygons. For each cell, perform some numpy operation (like rasterstats does) on the incoming polygons. I can perform pandas like operation after creating a geocube, but it doesn’t preserve the spatial object. I feel like the group_by argument is in this direction, but could not succeed.

Something like

#Turn each set of predictions into a raster
import geopandas as gpd
from shapely.geometry import Polygon
from geocube.api.core import make_geocube

#a numeric column to count
g["mask"] = 1

cube = make_geocube(vector_data=g, resolution=(-50, 50), function=mask.count())

To create a heatmap of number of polygons in each cell.

Here is a notebook to help illustrate use case (sorry the geocube svg doesn’t play well with ipython on github).

https://github.com/weecology/NEON_crown_maps/blob/master/notebooks/Create a raster of polygon counts.ipynb

[davidbrochart]

Fixed by passing all_touched=True:

rasterize_function=partial(rasterize_image, merge_alg=MergeAlg.add, all_touched=True)

[bw4sz]

yup. that did it. I’m away for the weekend, but i’ll try to fork and submit a notebook PR to add as a resource on monday. Thanks.

On Thu, Jun 18, 2020 at 8:12 PM Alan D. Snow [e-mail] wrote:

The second one is correct. I suggest doing cube.mask.plot()

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