SPEI notebook

[GvdDool]

Hi, I might be missing a resource, but I can't seem to locate a notebook where the SPEI is calculated, as an example. Having a notebook going through the calculation steps would be very useful, especially when the data is coming from another domain/source and will have to be pre-processed to fit the structure of the algorithm.

The read.me leads to a publication: https://www.researchgate.net/publication/252361460_The_Standardized_Precipitation-Evapotranspiration_Index_SPEI_a_multiscalar_drought_index, which is not publicly available, so checking the function would be extremely difficult without a notebook going through the calculation steps.

I checked the Palmer_Drought_Index notebook, and this notebook is well documented, and I understand the effort that goes into producing these notebooks, but having examples makes the library much more user-friendly.

I look forward to your comments, and I am more than happy to contribute to a notebook that handles data outside the Continental USA.