This belongs to [ComPlot](https://savannah.nongnu.org/projects/complot/). To use complot you need the program and the (larger) NetCDF data files. For versions below 1.1.0, those are both included in complot-*.tar.gz. If you checked out the ComPlot repository or are downloading version 1.1.0 or higher, you need complot_dsets.tar.gz additionally.