function getdata, un
	speed = 0
	result=0
	while not eof(un) do begin
		s=''
		readf, un, s
		s=strsplit(s,/extract)
		if n_elements(s) gt 4 then begin
			reads, s(3), speed
			result = [result, speed]
		endif
	endwhile
	
	return, result(1:n_elements(result)-1)
end