[daip] CLCAL bug

[Zsolt Paragi]

Dear Amy,

We found a bug in CLCAL, which seriously affects
experiments in which much Tsys data is missing.
Our problem is that there are timeranges where
Tsys measurements are lost at some EVN telescopes.
The script that processes the station logs places
"-2" into the input file for ANTAB (this is 999.9
in the case of the VLBA). APCAL creates an SN table
in which these instances are indicated with "INDE".
Unfortunately, CLCAL does not interpolate over
the timeranges with "INDE" entry.

This is probably not serious for the VLBA, because
missint Tsys data are not so frequent. But for
us it is a problem since long timeranges may be
flagged in the data for some telescopes. We tried
to play with the ANTAB input file replacing "-2"
with other numbers but it did not help. A short
term solution would be to modify the ANTAB files
for EVN users: we could replace "-2"s with fake
Tsys data, e.g. the last valid measurement. But
it would be best if CLCAL could do the job with
interpolating over these timeranges.

Sorry for bothering you with all of this, I hope
otherwise you have a great time with the baby!

Cheers,
Zsolt


======================================================================
  Zsolt Paragi                        |  Tel.   :  +31 521 596 536
  EVN Support Group                   |  Fax    :  +31 521 596 539
                                      |
  Joint Institute for VLBI in Europe  |  E-mail :  paragi at jive.nl
  Postbus 2, 7990 AA Dwingeloo, NL    |
======================================================================


On Tue, 8 Oct 2002, Eric Greisen wrote:

> The correct person to look at this is Amy and she will be back from
> maternity leave on Oct 28.  I get back on Nov 1 from my latest trip
> (ADASS, NRAO-CV, etc).  We have planned an overhaul of some of the
> interpolation things in CLCAL - but Tsys is a bad one to interpolate
> in that Tsys is quite often source dependent (backgroud emission,
> spillover etc etc)
>
> Eric Greisen
>