PRO dustem_old2new_ext_format, file=file

;NB: file should be the string of the old xcat file 

dustem_init

dir=!dustem_wrap_soft_dir+'/Data/EXAMPLE_OBSDATA/'

file=dir+file

str='cp '+file+' '+file+'.old'
spawn,str

old_ext=read_xcat(file,/silent,comments=old_comments)
Next=n_elements(old_ext)

new_ext=dustem_initialize_ext(Next,comments=new_comments,help=help)
comments=['Written by dustem_old2new_ext_format.pro on '+systime(0),old_comments,new_comments]

new_ext.instru=old_ext.instru
new_ext.filter=old_ext.filter
new_ext.wave=old_ext.wave
new_ext.EXT_I=old_ext.spec
new_ext.sigextII=(old_ext.error)^2

write_xcat,new_ext,file,comments=comments

END