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Updating the TPOINT model

Updating the TPOINT model


Pointing data files are held at the summit in directories/filenames like
/jac_logs/20050106/20050105-173329.pnt
Copy the relevant file into your working space.

Use the TPOINT commands to display the data with only collimations removed. If the residuals are large or show systematic trends with azimuth or elevation or other, then do a full 7-parameter model fit:

  • tpoint
  • indat yymmdd-hhmmss.pnt
  • inmod /home/imc/pointing/tpoint/data/jcmt.mod_070113
  • plton xw
  • fix
  • use ie ca ia npae aw an tf
  • fit
  • call a9   or   'g s a'   or   'g a a'   or   'g z z'   or   gdist,   gscat,   ghyst,   gsmap,   gdist,   gam etc
  • gc P to produce tpoint.ps of last plot
  • slist - to tabulate results and rms errors (dS,dZ)
  • mask (n) - to remove one datum, before repeating the fit
  • outmod new-model-name
  • end

           

If the fit is an good improvement - i.e. if dS,dZ are significantly smaller than after the fit using just IE & CA, and if the changes to any of the 7 parameters is significant at the 3-sigma level - then the updated values of the (7) model parameters should be entered into the file

          /jac_sw/itsroot/src/tcs/thi/THI.tide

on a summit machine, after which you should do

            source /jac_sw/itsroot/etc/login

            make

and then update the CVS.

Contact: Iain Coulson. Updated: Fri Feb 16 19:36:27 HST 2007

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