iraf.net

Hello,I often use doecslit within noao.imred.echelle in order to reduce my echelle data. What I would like to know is how to set a background region a-priori i.e. without using the 'b' key once I am running the package (or A,b to set all background apertures at once).I have tried setting e.g. b_sample=-40:-20,20:40 within apall, apdefault and apslitproc. Note that in sparams for echelle the b_sample does not seem to exist as it does for example in doslit.After running doecslit then b_sampl in apslitproc seems to get set back to the default values -16:-8,8:16. The values remain at -40:-20,20:40 within apall and apdefault but have no effect on the background regions that still seem to be set at the default -16:-8,8:16.In my uparm directory there is something called ecapslic that contains the line
eceapslic.par:b_sample,s,h,"-16.:-8.,8.:16.",,,">sparams.b_sample"...but if I edit it with -40:-20,20:40 and then run doecslit it just gets set back to -16:-8,8:16.Finally if in the IRAF cl I try:
ec> sparams.b_sampl='[-40:-20,20:40]'
...I get: ERROR: parameter 'b_sampl' not found.Is there something obvious I am missing? Thanks!
Jonathan

Hello Jonathan,When you run doecslit it automatically sets several things based on the width parameter:[code:1:18be43d647]
apslitproc.width = width
apslitproc.lower = -width / 2.
apslitproc.upper = width / 2.
apslitproc.b_sample = \
str(-2*width)//":"//str(-width)//","//str(width)//":"//str(2*width)
apslitproc.t_width = width
apslitproc.radius = width
apslitproc.minsep = width
[/code:1:18be43d647]So anything you set separately, say in apslitproc, will be changed when your run doecslit. I cannot remember specifically but it must have seemed like a good idea to minimize the number of things a basic user has to worry about. One has to keep in mind that the DO tasks were targeted at the basic user and not the power user.A suggestion for how you can change this for yourself is as follows.1. Copy imred$src/doecslit/doecslit.cl to your home directory.
2. Edit or comment out the b_sample line.
3. Load the echelle package
4. Redefine the task with: redefine doecslit=home$doecslit.clYours,
Frank Valdes