Does anyone know of an R code to calculate Palmer Drought Severity Index (PDSI)?

A tool has been created for MatLab:

Jacobi, J., D. Perrone, L. L. Duncan, and G. Hornberger (2013), A tool for calculating the Palmer drought indices, Water Resour. Res., 49, doi:10.1002/wrcr.20342.

This is the link for .exe file / C++ code that achieves the same.

It contains a manual that describes the input/ output file formats.

I hope that someones skilled enough can write a wrapper for this

http://greenleaf.unl.edu/downloads/

It looks like we can thank Christian Zang for finally solving the problem: https://github.com/cszang/pdsi

Edit from 2018: This answer was just accepted so I have decided to fork the above-linked repo to my github to guard against future link rot. It will stay there indefinitely.

Now library scPDSI is available in R for calculation of Palmer Drought Severity Index.