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problems running loop_driz

Francesca Annibali wrote on Jul 19, 2011

Dear user support,

I am trying to run the loop_driz task on non-HST images.
I get the following error:

ERROR: Attempt to access undefined local variable `gcount'.

"if (gcount == 4) {"
line 184: dither$loop_driz.cl
called as: `loop_driz (input=@img_C2.list, output=bla.fits, masks=@mask_C2.list, shiftfile=shifts.C2.txt, shifttask=shiftfind, verbose=yes)'

Can you help me with this problem?

many thanks,

Francesca

Mike Fitzpatrick wrote on Jul 19, 2011

The 'gcount' keyword is probably missing from your image. This is read from the header and scanned into a script variable, but if it doesn't exist you'll typically see the 'undefined local variable' message.

Since these are non-HST images you should use HEDIT to add the gcount keyword with a value other than 4.

Last post on Jul 19, 2011