Software Documentation

Distortion calculations

One of the main features implemented in this program is the ability to include long-range wavelength-scale distortions to quasar spectra and look at the impact on the absolute chi-square and varying alpha fits through VPFIT. Since this particular set of tools might be useful for many other research projects, we made a standalone Python script that can be executed without the need to import the whole alphaqso library. The download link below will allow you to download directly the script without having to clone the entire gitlab repository or install the whole library on pip (do right click and select Save Link As… to download the file):

Download script

Below we list all the functions and classes present in the script. The links below will take you to more detailed descriptions of the functions and classes where all input parameters, returned variables and methods are listed along with links to the source code and some examples on how to execute the operation.

Common functions

isfloat (value)

Check if variable is of float type or not, return boolean value.

getshift (explist, left, right, slope[, random])

Calculate velocity shift do to distortion depending on model used.

Main classes

The 3 main operations (i.e. building the model, do the calculations, and plot the results) will be carried out by 3 different classes.

DistModel (fort13, explist[, slope, output])

Create distortion model.

AlphaDist (fort13, explist[, distmin, …])

Main method to execute all distortion calculations.

PlotCurve ([thermal, turbulent, distmin, …])

Plot chi-square curves.