  The eXtended CASA Line Analysis Software Suite (XCLASS) is a toolbox for the
Common Astronomy Software Applications package (CASA) containing new functions
for modeling interferometric and single dish data. Among the tools is the
myXCLASS program which calculates synthetic spectra by solving the radiative
transfer equation for an isothermal object in one dimension, whereas the finite
source size and dust attenuation are considered as well. Molecular data
required by the myXCLASS program are taken from an embedded SQLite3 database
containing entries from the Cologne Database for Molecular Spectroscopy CDMS)
and JPL using the Virtual Atomic and Molecular Data Center (VAMDC) portal.
Additionally, the toolbox provides an interface for the model optimizer package
Modeling and Analysis Generic Interface for eXternal numerical codes (MAGIX),
which helps to find the best description of observational data using myXCLASS
(or another external model program), i.e., finding the parameter set that most
closely reproduces the data.
