Minimum finding algorithm seems to have a slight error

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Exact minimum point is a bit off — what is going on here?

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In the separatrix_operational_space.ipynb notebook, you can see what is causing this issue. Where there are multiple points fulfilling the mask condition with the same value, the code is returning the first value it finds.

from cfspopcon.shaping_and_selection import find_coords_of_minimum

dataset["SepOS_LH_transition"].T.plot(vmin=0.9, vmax=1.1)
dataset["SepOS_LH_transition"].T.plot.contour(levels=[1.0])

point = dataset.isel(find_coords_of_minimum(dataset["separatrix_electron_temp"], mask=dataset["SepOS_LH_transition"] > 1.0))

plt.scatter(point.separatrix_electron_density, point.separatrix_electron_temp, color="r")

plt.ylim(50, 70)

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Increasing the resolution is a simple solution, i.e. 10x increase in both dimensions