BUG: scipy.optimize.curve_fit full_output and boundaries incompatible about scipy

[nickodell]

It appears you are using SciPy 1.6.2, which is about three years old, and which does not support the full_output argument to curve_fit().

Here is why I think this:

I first tried reproducing your problem with the latest version of SciPy, 1.13.1. I found that I could not reproduce it in that version.

I then went back, to find which version of SciPy fixed this issue. I found that 1.8.1 failed, but 1.9.0 worked.

With this, I went looking at the release notes for 1.9.0, to see if someone had fixed this in 1.9.0. Searching for full_output, I found this:

Add a full_output parameter to scipy.optimize.curve_fit to output additional solution information.

This seems like an issue that we have fixed already in SciPy 1.9.0.

For that reason, I suggest you upgrade to a version of SciPy with support for full_output.