IDL Commands Text File

Following is a set of IDL commands to read and display SSM/I brightness
temperature or sea ice concentration grids:

IDL> data = bytarr(304,448)	;grid dimensions for northern polar region
IDL> openr,lun,'file path',/get_lun
IDL> readu,lun,data
IDL> tvscl,data	;order=1 may be necessary to rotate file  

Another method of reading a sea ice concentration grid:

IDL> hdf_dfr8_getimage,'file path',data
IDL> tvscl,data

Other useful commands:

IDL> loadct,13  ; adds a color table if desired
IDL> print,min(data),max(data)  ; to view min,max values
IDL> rdpix,data ; read cursor value

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Reading latitude and longitude grids:

IDL> lats = lonarr(304,448)  ;grid dimensions for northern polar region
IDL> openr,lun,'psn25lats_v2.dat',/get_lun
IDL> readu,lun,lats
IDL> lats = lats/100000. ; to scale by 100000 and return an integer

IDL> lats = lonarr(316,332)  ;grid dimensions for northern polar region
IDL> openr,lun,'pss25lats_v2.dat',/get_lun
IDL> readu,lun,lats
IDL> lats = lats/100000. ; to scale by 100000 and return an integer

IDL> lons = lonarr(304,448)  ;grid dimensions for northern polar region
IDL> openr,lun,'psn25lons_v2.dat',/get_lun
IDL> readu,lun,lons
IDL> lons = lons/100000. ; to scale by 100000 and return an integer

IDL> lons = lonarr(316,332)  ;grid dimensions for northern polar region
IDL> openr,lun,'pss25lons_v2.dat',/get_lun
IDL> readu,lun,lons
IDL> lons = lons/100000. ; to scale by 100000 and return an integer