function d_MOMENT, vec
;
;   shortened version of MOMENT, designed for fast use by
;   median_filtered_mean routine
;
;   returns mean and variance
;
;   DPC   20051023  original code
;
mean = dblarr(2)
nv = size(vec)
nv = nv[1]
fnv = double(nv)
;
;   compute sums
;
mean[0] = TOTAL(vec,/DOUBLE)
mean[1] = TOTAL(vec*vec,/DOUBLE)
;
mean[0] = mean[0] / fnv
;
mean[1] = (mean[1]/fnv) - mean[0]*mean[0]
;
return, mean
end