function model, filename		;returns the DISR model of the dataset
; created 8/4/96, csee

if strpos(filename,'Ir') ne -1 then goto,ir

d_read,filename,h0,p0
n=d_value(h0,219)
goto,exit

ir:
d_irread,filename,h0,p0,g0
n=d_value(h0,219)

exit:
return, n
end