rand_probability=$(expr $(expr $weight \* 1000) / $total_weight)
roundlen=`expr length $rand_probability - 1`
roundme=${rand_probability:$roundlen}
-rand_probability=$(echo $rand_probability | sed s/$roundme//)
+rand_probability=$(echo $rand_probability | sed 's/\(..\)\(.\)/\1/g')
if [ $roundme -ge 5 ]; then
rand_probability=$(expr $rand_probability + 1)