ARTS built-in documentation server

Workspace Method SpeciesSet

Description

Set up a list of absorption species tag groups.

Workspace variables like abs_species contain several tag
groups. Each tag group contains one or more tags. This method converts
descriptions of tag groups given in the keyword to the ARTS internal
representation (an ArrayOfArrayOfSpeciesTag). A tag group selects
spectral features which belong to the same species.

A tag is defined in terms of the name of the species, isotope, and a
range of frequencies. Species are named after the standard chemical
names, e.g., "O3". Isotopes are given by the last digit of the atomic
weight, i.g., "O3-668" for the asymmetric ozone molecule including an
oxygen 18 atom. Groups of transitions are specified by giving a lower
and upper limit of a frequency range, e.g., "O3-666-500e9-501e9".

The symbol "*" acts as a wild card. Furthermore, frequency range or
frequency range and isotope may be omitted.

Finally, instead of the isotope the special letter "nl" may be given,
e.g., "H2O-nl". This means that no absorption at all is associated
with this tag. (It is not quite clear if this feature is useful for
anything right now.)

This method used to be a specific method for abs_species. Now it is
generic, so that it can also be used to set abs_nls and *abs_pts*.

Example:

   species = [ "O3-666-500e9-501e9, O3-686",
               "O3",
               "H2O-PWR98" ]

   The first tag group selects all O3-666 lines between 500 and
   501 GHz plus all O3-686 lines. 

   The second tag group selects all remaining O3 transitions.

   The third tag group selects H2O, with one of the complete
   absorption models (Rosenkranz 98). No spectrocopic line catalogue
   data will be used for that third tag group.

Authors: Stefan Buehler

Synopsis

Variables