function eit_gt_wavelnth, header, image_no=image_no, debug=debug ;+ ; Name: ; eit_gt_wave ; ; Purpose: ; Return the wavelength of a 2- or 3-D index structure or ; FITS header. ; ; Input Parameters: ; header = FITS header or EIT index structure for image ; ; Input Keywords: ; image_no = Image number from within above header ; ; Output: ; wavelength of chosen image ; ; Calling Sequence: ; wave = eit_gt_wavelnth(fits_header) ; wave = eit_gt_wavelnth(fits_header,image_no=7) ; wave = eit_gt_wavelnth(index [,image_no=4]) ; ; Running Commentary: ; Another workaround for fits keywords disguised as comments. ; ; History: ; 3-November-96 - (BNH) - Written ;- if (n_elements(header) eq 0) then begin message, /info, 'No index/fits header supplied!' return, -1 endif case gt_tagval(header, /naxis) of 2: return, gt_tagval(header, /wavelnth) 3: case data_chk(header, /type) of 7: return, eit_fxpar(header, 'WAVELNTH', image_no=image_no) 8: return, gt_tagval(index(image_no), /wavelnth) else: begin message, /info, "Passed value is not a valid header or index structure." return, -1 end endcase endcase end
Last revised: - Wed May 9 21:45:19 2007- F. Auchère