Using xrt

Scripting in python

You need to prepare a script that gives instructions on how to get the wanted ray properties and prepare the graphs. The scripting is different for different backends (backend is a module or an external program that supplies ray distributions). Currently, xrt supports two backends: raycing – an internal backend – and shadow.

Please consider the supplied examples.

Running a python script

You can run it from your shell as python your-script.py or from within an IDE, e.g. Spyder.

Interacting with the plots

matplotlib provides an interactive navigation toolbar that allows zoom, pan and save functions.

Saving the results

You can save a plot using its navigation toolbar or by specifying the parameter saveName of the plot in your Python script.

You can also save any of the plot attributes through a script. For this, use the parameter afterScript of xrt.runner.run_ray_tracing to point to a function that will be executed after all the repeats have been completed. A typical usage of such a function is to pickle 1D and 2D histograms, fwhm values etc. For example:

• plot.xaxis.total1D is the 1D histogram of xaxis of plot. Use an appropriate axis, there are three available: xaxis, yaxis and caxis.

• plot.xaxis.binCenters and axis.binEdges are the edges and centers of xaxis bins

• plot.total2D is the 2D histogram

• plot.total4D is the 4D mutual intensity, see fluxKind for the appropriate options

• plot.dx, plot.dy and plot.dE store fwhm’s of the three 1D histograms

• flux or power are accessed as plot.flux and plot.power