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specifying wavelength ranges for fxcor

Philip Massey wrote on Jan 14, 2008

Hi, Mike et al---

I'm using fxcor for the first time in a couple of years, and need to remind myself how to specify the wavelength range for my program objects and standard velocity templates. The data are dispersion corrected, of course. I want
to restrict the cross correlation to the regions 4500-5500A and 5700-6500A,
say. My reading of the help page suggests that all I have to do is specify
"4500-5500,5700-6500" for osample and rsample. But, my memory is that it's
more complicated than that. Do I need a preceeding "A"?
I can't tell from the results whether it's done what I've asked or not (i.e., there's nothing on the *.txt" output that indicates the
wavelength region has been restricted).

thanks,
phil

Mike Fitzpatrick wrote on Jan 14, 2008

Hi Phil,

A range in angstroms is assumed if no 'a' or 'p' preceeds the ranges and the data are dispersion corrected. To check the values, you can use the 's' key to get into Spectrum Mode and you'll see the wavelength ranges marked for each spectrum. I believe they are also printed in the log shown with the 'v' keystroke.

Cheers,
-Mike

Last post on Jan 14, 2008