Check if polygon intersects with coordinates in a .csv file with PyQGIS standalone script

Question

I have a bunch of .csv files with coordinates and a polygon. In my standalone script I would like to check if the polygon intersects with the coordinates.

So, when I write:

            for feature in polygon.getFeatures():
                if feature.geometry().intersects(file.geometry()):

It doesn't work because the coordinates in my 'file' are of type string and not a QGIS Rectangle.

I can use numpy to sort of get the extent of the coordinates as string by writing:

        data = np.genfromtxt(file, delimiter=" ")
        x = data[:, 0]
        y = data[:, 1]

        xmin = min(x)
        xmax = max(x)
        ymin = min(y)
        ymax = max(y)

I feel like I have all the extents but now I need to find a way to check if they intersect. I'm stuck at this point. How can I do this?

I'm using QGIS 3.10.

Answer 1

You can create a map layer from each CSV file (read the docs).

import glob

for file_path in glob.glob("/path/to/csv/folder/*.csv"):
    uri = "file://{}?delimiter=;&crs=epsg:3116&xField=x&yField=y".format(file_path)
    csv_layer = QgsVectorLayer(uri, file_path, 'delimitedtext')

Then (still inside that for) you can get each layer's extent and check the intersection.

for polygon_feature in polygon_layer.getFeatures():
    if polygon_feature.geometry().intersects(csv_layer.extent()):
        print("File '{}' intersects!".format(csv_layer.name()))       

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Note: You seem to have a polygon layer and not just one polygon geometry. If that's the case you'll end up with nested for loops. Otherwise, if you have a single polygon geometry, you will just need a single for to iterate csv files.