Graf has been developed over the years as in in-house plotter for astrophysicists, and scientists in general by Prof Ralph Sutherland at Mt Stromlo Observatory.
The philosophy is that the data may come from any source in basic text form with notional columns. Graf reads the files on the fly, looking for numbers to plot and ignoring text it cant plot. This makes it very useful for when data is not conveniently already in a column-spreadsheet format, although it can happily use .csv files as well.
A data window is opened and multiple setups with columns, colours, markers, line styles and transformations can be defined.
A plot window can plot all the data sets from any number of data windows, applying a plot style and plot transform, including affine 3D rotations.
Stat windows can perform basic numerical analysis of the selected data sets, including basic statistics, linear and non-linear regressions, splines, FFTs, convolutions and histogram analysis.
The plots can be combined using drag and drop between plot windows, and the output PDF are small and high quality, and have been used in mainstream scientific journals and PDF LaTeX documents for many years.
Graf0 runs on older machines often found at universities without upgrade processed, and will work back to system 10.9, Mavericks. A new Graf version is in development to take advantage of new macOS features and will require newer operating systems, but will maintain backward file compatibility as a priority.
Graf is highly sandboxed and no network or access to any files or hardware except general text, Graf and output graphics.