This is a fork repository from https://github.com/wfpidn/SPI which originally developed during my service with WFP, and since I left the agency this guideline no longer maintained. So I will continue to update this at my personal Github repo.
The SPI analysis is following the training conducted in 28 Jan 2020 by NASA ARSET on Application of GPM IMERG Reanalysis for Assessing Extreme Dry and Wet Periods. Link: https://appliedsciences.nasa.gov/join-mission/training/english/arset-applications-gpm-imerg-reanalysis-assessing-extreme-dry-and-wet
Follow the complete guideline here:
https://bennyistanto.github.io/spi
Thanks to Yanmarshus Bachtiar for CDO's tips and Ridwan Mulyadi for IMERG shell script.