RuntimeWarning: invalid value encountered in divide x_2 = (-b__ - np.sqrt(discriminant)) / (2 * a__)

Code Sample, a minimal, complete, and verifiable piece of code

I have a temperature grib message and I want to resample it using cubic resampling. However, i get these warnings in the console. If i lower the radius value I no longer get the warnings but I get 0s in the interpolated data.

 UserWarning: You will likely lose important projection information when converting to a PROJ string from another format. See: https://proj.org/faq.html#what-is-the-best-format-for-describing-coordinate-reference-systems
  proj = self._crs.to_proj4(version=version)

RuntimeWarning: invalid value encountered in divide   x_2 = (-b__ - np.sqrt(discriminant)) / (2 * a__)

import numpy as np
from pyproj import CRS
from pyresample.geometry import GridDefinition
from pyresample import create_area_def
from pyresample.bilinear import NumpyBilinearResampler
from pyresample import geometry


data = np.fromfunction(lambda y, x: y * x, (100, 100))
lons = np.fromfunction(lambda y, x: -180 + x * 3.6, (100, 100))
lats = np.fromfunction(lambda y, x: -90 + y * 1.8, (100, 100))


source_def = geometry.GridDefinition(lons=lons, lats=lats)

crs = CRS.from_epsg(3857)  # EPSG code for WGS 84 / Pseudo-Mercator
target_def = create_area_def('my_area',
        crs,
        1000, 1000,
        area_extent=[-180, -85, 180, 85],                
        units='degrees',
        description='Target grid in Mercator projection')


resampler = NumpyBilinearResampler(source_def, target_def, radius_of_influence=200000)
interpolated_data = resampler.resample(data)

Thank you!

Start by running the supplied Python example and inspect NumpyBilinearResampler.resample where the RuntimeWarning appears during cubic or bilinear resampling. Compare the behavior with different radius_of_influence values and investigate the projection and grid definitions shown. Done means the warning's cause is addressed and interpolation no longer silently produces zeros for the reported case.