========
TARG_DIR
========

:envvar:`TARG_DIR` is the root directory for catalogs of targets, gfas,
skies, randoms, pixweight files (files of quantities from the random
catalogs averaged across HEALPixels) and QA (quality assurance) webpages.
The canonical location is ``$DESI_ROOT/TS/target/catalogs`` but the
environment variable :envvar:`TARG_DIR` can be set to point anywhere.
Here, ``TS`` is, e.g., ``public/ets`` for DESI early target selection.

Under :envvar:`TARG_DIR`:

- Target catalogs derived from DESI Legacy Surveys imaging are grouped by
  the imaging Data Release (DR) as a drX.Y string. The X refers to the
  primary Data Release integer and the Y is only rarely used for critical
  reprocessing of a Data Release (*e.g.* dr7.1).
- Target catalogs derived solely from Gaia are in the ``gaiadr2`` directory.
- Fixed subpriorities assigned for the DESI Main Survey (see Section
  5.2 of the Myers et al. DESI Target Selection Pipeline paper) are
  stored in the ``subpriority`` directory.

Subdirectories:

.. toctree::
   :maxdepth: 1

   DR/index
   gaiadr2/index
   subpriority/index