Tim Jenness
and 1 contributors


Astro::FITS::HdrTrans::JCMT_GSD_DB - JCMT GSD Database header translations


Converts information contained in JCMT heterodyne database headers to and from generic headers. See Astro::FITS::HdrTrans for a list of generic headers.



Returns true if the supplied headers can be handled by this class.

  $cando = $class->can_translate( \%hdrs );

For this class, the method will return true if the "GSDFILE" header exists and the "SCA#" header exist.


These methods are more complicated than a simple mapping. We have to provide both from- and to-FITS conversions All these routines are methods and the to_ routines all take a reference to a hash and return the translated value (a many-to-one mapping) The from_ methods take a reference to a generic hash and return a translated hash (sometimes these are many-to-many)


Sets the INSTRUMENT generic header. For RxA3i, sets the value to RXA3. For RxB, sets the value to RXB3.


Calculate a unique Observation ID.


Translates the DATE_OBS or LONGDATEOBS header into a YYYYMMDD integer.


Translates the DB date header into a Time::Piece object.


Translates the database date header into a Time::Piece object and adds on the exposure time.


Uses the NORSECT (number of backend sections), NOFCHAN (number of frontend output channels) and NOBCHAN (number of channels) to form a string that is of the format 250MHzx2048. To obtain this, the bandwidth (250MHz in this example) is calculated as 125MHz * NORSECT / NOFCHAN. The number of channels is taken directly and not manipulated in any way.

If appropriate, the bandwidth may be given in GHz.


Translate the VREF and C12VDEF headers into one combined header.




Brad Cavanagh <b.cavanagh@jach.hawaii.edu>, Tim Jenness <t.jenness@jach.hawaii.edu>


Copyright (C) 2008 Science and Technology Facilities Council. Copyright (C) 2003-2007 Particle Physics and Astronomy Research Council. All Rights Reserved.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place,Suite 330, Boston, MA 02111-1307, USA