`NotFittedError` after caching and reloading fitted `Ivis` instance about ivis

[Szubie]

Thanks for reporting this.

I will look into making Ivis models serializable using pickle, is sounds like a useful feature if we can do it. Hopefully that will solve the issues you're encountering.

[imatheussm]

I was coding a solution here, which consisted in renaming the currently defined Ivis.__getstate__() to Ivis._get_json() and creating new Ivis.__getstate__() and Ivis.__setstate__() methods. The solution consisted in the following:

• In Ivis.__getstate__(), the internal dictionary state would be obtained. However, for the encoder_, model_, neighbour_matrix_, and supervised_model_ attributes, the following procedure would be adopted: .save() would be called for each of them, generating a annoy.index file for neighbour_matrix_ and .h5 files for the rest. Then, using the built-in base64 module, these files would be encoded into a Base64 string, which would be attributed to the respective parameters.
• In Ivis.__setstate__(), the same four parameters described above would be checked. If present, base64 would be used to decode them into the binary files they originally were. Then, they would be used to load the original parameters back into their respective attributes.

However, I stumbled in a problem: when calling Ivis.neighbour_matrix_.save(<path>), or even Ivis.neighbour_matrix_.index.save(<path>), no file was produced, regardless of path type (absolute or relative) or file name. I am currently assuming this is an annoy-related issue.

I am just posting this in case this reasoning is helpful to you.