Versioning of Calibration Constants

   To get reproducible reconstruction results it is necessary not only to
   have a stable version of the reconstruction software, but also a stable
   version of the calibration constants. At some point in the future we
   will have a calibration database that will allow a reproducible choice
   of a set of constants. At present however, the constants are kept in
   the Subversion repository. This is an interim measure. Given the
   situation, the current scheme relies on the versioning provided
   natively by Subversion.

Contents

     * 1 Checking out the versions
          + 1.1 Current constants
          + 1.2 Versions by date or Subversion revision number
          + 1.3 Tagged versions of the calibration constants
     * 2 Pre-checked-out versions at JLab
          + 2.1 Old location of the calib directory
     * 3 Setting the JANA_CALIB_URL environment variable

Checking out the versions

   Here is what is available.

Current constants

   The current set of all constants are in directory tree
   [12]https://halldsvn.jlab.org/repos/trunk/calib. All new versions of
   constants should be checked into this area.

Versions by date or Subversion revision number

   Older versions of the constants can be obtained by specifying the
   --revision (-r) option. For example:

svn checkout --revision 5432 [14]https://halldsvn.jlab.org/repos/trunk/calib

   checks out revision 5432 and

svn checkout --revision '{2009-08-28}' [15]https://halldsvn.jlab.org/repos/trun
k/calib

   checks out the version at the start of August 28, 2009. These versions
   are there just by virtue of the file being kept in the repository.

Tagged versions of the calibration constants

   Tagged versions are kept in the repository in the directory
   [17]https://halldsvn.jlab.org/repos/tags. They have descriptive names
   such as "calib-2010-03-10", and generally match the naming scheme of a
   tagged release of sim-recon. These tags are created by hand (they are
   not "naturally occurring" in Subversion).

Pre-checked-out versions at JLab

   On the JLab CUE there some versions checked out on the halld group
   disk. They are in the directory /group/halld/Software/calib. Currently,
   the latest version and the tagged versions are there:

> ls -l /group/halld/Software/calib/
total 12
drwxr-sr-x 10 gluex halld 4096 Mar 15 14:11 calib
drwxr-sr-x  8 gluex halld 4096 Mar 15 14:21 calib-2010-02-11
drwxr-sr-x 10 gluex halld 4096 Mar 15 14:22 calib-2010-03-10
lrwxrwxrwx  1 gluex halld    5 Mar 15 14:11 latest -> calib

   Note that "latest" is actually a link to a version checked out from the
   trunk. This version is updated daily at midnight.

Old location of the calib directory

   Up until March 16, 2010, there was only one calib version checked out
   for public use at JLab. It was located at /group/halld/calib and would
   get updated occasionally. This location now contains a link to the
   latest version (for backward compatibility of old environment
   settings).

Setting the JANA_CALIB_URL environment variable

   To use a particular checked-out version of the calibrations, you set
   the JANA_CALIB_URL environment variable to point to the top-level
   directory. For example, at JLab, to use the latest version of the
   constants you say

setenv JANA_CALIB_URL file:///group/halld/Software/calib/latest

   Retrieved from
   "http://www.jlab.org/Hall-D/software/wiki/index.php/Versioning_of_Calibration_Constants"