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I've a geopandas dataframe stored with X, Y coordinates, their latitude and longitude equivalent and their geometry as points. Data snippet:

             long     lat    X    Y      geometry
55898  -45.520195 -18.571566  151  179    POINT (-45.52019 -18.57157)
55902  -45.520227 -18.582375  151  183    POINT (-45.52023 -18.58238)
55910  -45.520293 -18.603994  151  191    POINT (-45.52029 -18.60399)
56267  -45.517361 -18.571574  152  179    POINT (-45.51736 -18.57157)

What I'd like to do is to unite 4 points sequentially, that is following the order in the dataframe, so I can get the coordinates of a square. The desired output doesn't really need to contain the other columns, just the geometry of a polygon, it would be similar to this:

1    POLYGON ((977855.4451904297 188082.3223876953,...
2    POLYGON ((1017949.977600098 225426.8845825195,...
3    POLYGON ((988872.8212280273 146772.0317993164,...
4    POLYGON ((1000721.531799316 136681.776184082, ...
5    POLYGON ((915517.6877458114 120121.8812543372,...
PCosme
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1 Answers1

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One should provide the lat and lon coordinates as a nested list to the Shapely Polygon object. See https://stackoverflow.com/a/30461816/12987768

With gdf being the GeoDataFrame:

    from shapely.geometry import Polygon

    rows_numbers= [i for i in range(0, len(gdf), 4)]
    polygons = []

    for idx, _ in enumerate(rows_numbers):
        if idx == len(rows_numbers)-1:
            print("end of gdf")
            break
        polygon_coords = []
        for point in gdf.geometry.values[rows_numbers[idx]: rows_numbers[idx+1]]:
            polygon_coords.append([point.x, point.y])
        polygons.append(Polygon(polygon_coords))

with the resulting polygons list containing the 4-point Polygons

TDeg
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