relerr=av(*,*,7)/av(*,*,2)
wall=where(count ne 0)
w75=where(count ge 0.75*nav)
sigall=sqrt(1/total(1/relerr(wall)^2))
sig75=sqrt(1/total(1/relerr(w75)^2))

print,sigall,sig75
print,1/sigall,1/sig75

end