After the `allocate mtn' command (Reading FITS files from tape)
cl> xray xr> xdataio xd> xrfits mtn 3 visitor_a # load tape file 3 and name it visitor_a.imh xd> xrfits mtn 1-10 visitor # load files 1 to 10 in visitor_0001 # to visitor_a.imh frame visitor.0001 average frame [300,500] # One line like this per # file loaded # .headers will be loaded in the working directory # *.pix files (the images) will be loaded in the image directory xd> xrfits mtn 11,13-14 visitor # A different loading commandIf you have image arrays written by MIDAS, use mperfits:
xd> mperfits mtn 1-3 images # Convert the first three files on tape device mtn
When you have finished loading your files,
xd> rewind mtn xd> deallocate mtn # IRAF release of tape drive To dismount the tapes at SAO: cfa250: rlsdev mtn #release the tape drive cfa250: logout #logout of reel
N.B.#1: File numbers in a single xrfits call must be in increasing order.
N.B.#2: To list the names of files 1 to 10 without loading the files, use rfits in dataio.
da> rfits mtn 1_10 make_im=no
N.B.#3: Dimensions of FITS Arrays.
There is sometimes trouble with dimensionality of FITS images. IRAF likes images to have 2 dimensions. To use imlintran, etc. if the input image thinks it has dimensions 3,4,..., it is necessary to copy the image and to modify the header. To find out the dimensionality of an image, type
im> imhead velalow # gives short header for the image ``velalow'' velalow [512:512:1][real]:EINSTEIN XRAY DATA # this response indicates # 3 dimensions
or this response might be,
velalow [512:512][real]:EINSTEIN XRAY DATAwhich indicates 2 dimensions, a satisfactory input for iraf tasks.
If more than 2 dimensions, type
im> imcopy velalow[1:512,1:512] velalow # will make 2 dimensional imageThe parameter WCSDIM in the header must also be changed
im> hedit images: velalow field: WCSDIM value(3): 2 WCSDIM 3>2: <cr> update velalow (yes): <cr> im>