Functions for calculating K-corrections.
To define the calculation you must choose both a filter,
specified as a KCF_*
constant,
and a colour (filter pair) specified as a KCC_*
constant.
For each available filter, only certain colours are available,
as described in the documentation of the relevant KCF_*
constant.
The algorithm used is described at http://kcor.sai.msu.ru/. This is based on the paper "Analytical Approximations of K-corrections in Optical and Near-Infrared Bands" by I.Chilingarian, A.-L.Melchior and I.Zolotukhin (2010MNRAS.405.1409C), but extended to include GALEX UV bands and with redshift coverage up to 0.5 as described in "Universal UV-optical Colour-Colour-Magnitude Relation of Galaxies" by I.Chilingarian and I.Zolotukhin (2012MNRAS.419.1727C).