Hello, as the bug tracker seems to be flooded with spam, I post this here:
The built-in interpolation functions don't work with units in the third argument. The proposal is to modify the functions such that they can handle units.

The interpolation functions from Mathcad toolbox don't fail when the sampling point has units but they also ignore the units of the second argument.
PS: I'd be ready to clean up a bit in the bug tracker. What would be the appropriate way to do it?
Martin KraskaPre-configured portable distribution of SMath Studio: https://en.smath.info/wiki/SMath%20with%20Plugins.ashx