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Hello Peter,Use the slist task. You can select a single aperture and pipe the output to scan or you can dump the information into a file and then a loop over each line of the file. For the SNR I assume you mean finding the mean and rms of the continuum. It depends on whether you want to do this interactively or automatically and whether you have specific wavelength regions. Interactively this is usually done with splot though you need to do a continuum normalization or subtraction if there is any slope to the continuum. If you have specific wavelength ranges then you can use bplot and put the wavelengths into a cursor file. For echelle the logic is a bit tricky because each order has a different wavelength coverage. Finally to do things automatically you would probably use continuum to produce the data output minus the lines and then use imstat. Again you would need to use image sections or scopy to keep the orders separate if you have them all in a single .ec file.I hope this helps,
Frank ValdesOn Apr 28, 2010, at 12:12 AM, Piotrek Konorski wrote:> Dear Frank,
>
> I'm really sorry for bothering You with this.. Could You help me with
> a little IRAF problem?
>
> I'm trying to write a script in IRAF dealing with echelle spectra and
> I wonder if there is a way to get dispersion information (aperture,
> order, wavelength range) for each aperture into variables..? It is
> printed to screen when doing dispcor but is there a way to obtain them
> these values?
>
> Btw do You know what is the easiest but accurate way to calculate SNR
> for echelle spectra using IRAF?
>
> Thank You very much,
> Peter Konorski