function cdf_var_exists, cdf, varname
if data_type(cdf) eq 7 then id = cdf_open(cdf) else id = cdf
var_exists = 0
inq = cdf_inquire(id)
for i = 0, inq.nvars - 1 do begin
varinq = cdf_varinq(id, i)
if varinq.name eq varname then begin
var_exists = 1
goto, endofloop
endif
endfor
for i = 0, inq.nzvars - 1 do begin
varinq = cdf_varinq(id, i, /zvariable)
if varinq.name eq varname then begin
var_exists = 1
goto, endofloop
endif
endfor
endofloop:
if data_type(cdf) eq 7 then cdf_close, id
return, var_exists
end