The documentation for scipy.interpolate.interp1d tells me
This class is considered legacy and will no longer receive updates. This could also mean it will be removed in future SciPy versions. For a guide to the intended replacements for
interp1dsee 1-D interpolation.
The linked page basically tells me to use numpy.interp for piecewise linear interpolation. However, as far as I can tell, that function does not support linear extrapolation beyond the data range (only constant extrapolation). This makes it an inadequate replacement where linear extrapolation is desired.
What is the recommended replacement for interp1d in those cases, now that it is no longer recommended for new code?