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I would love to hear from anyone who can comment on and help me fix this error that I received while trying to bring up a subtracted image. Basically, I subtracted one image from another and created a new file. When I try to bring up that file using "implot sub019a" it gives me a segmentation error. I am using Fedora and v2.14. The new file is in the same directory as the original images. Any thoughts? Thanks in advance.

A segfault is usually a coding error, but in some cases can be caused by the data. Does an IMSTAT on the image manage to read it successfully or do you see a similar segfault. Did you do the subtraction with IMARITH or something else?If no other task can read the image either then it's the data: You can force the image to be a different format using e.g.[code:1:fd17c70bf0]cl> imarith im1 - im2 result.fits[/code:1:fd17c70bf0]If you can then implot/imstat the 'result.fits' check your 'imdir' variable: This is where the .pix files for IMH format images are stored and in your case may not be valid or writable.OTOH if it's only implot that's failing, please post a url to the image or put it in the anonftp at ftp://iraf.noao.edu/pub and I'll try to reproduce the problem.Cheers,
-MikeP.S. Also be sure you're using the Jan14 critical update mentioned on the homepage, that usually causes a different error but better to check anyway.

I used IMARITH to do the image subtraction (a .fits file minus a .fits file). IMSTAT gives a "cannot read or open" fault. When I save the file as a .fits image, I can open it, but this doesn't help as I need it in a .imh format for the APALL commands I need to do.My "imdir" is defined, but not as the file in which my data is saved. Is that a problem? I posted the 'spec019a.imh' image file on the FTP you posted in hopes that we can figure this out... thanks for your help! -Steve

The image you posted has the pixel file has just an empty string, i.e. what you have is a header but no pixels.What *is* the value of your 'imdir' variable (i.e. "cl> show imdir")? Is this a directory you can write to and that actually exists?A simple test is to rest the imdir to something known like the directory where the image is being created:[code:1:f53c5cdd88]
cl> reset imdir = "HDR$/"
cl> flpr 0 # zero, not oh
cl> imarith one.fits - two.fits result.imh
cl> imstat result.imh
[/code:1:f53c5cdd88]You can reset the imdir by editing your login.cl file, note that a value like "HDR$pix/" (trailing '/' required!) will create a 'pix' subdirectory and put the pixel files there.-Mike

Looks like that did it. Thanks for your prompt and helpful replies!-Steve