while true; do read str; if [ "$str" == "" ]; then break; fi; i=$[$i+1]; echo $str  $i; done < APRIL.messung0203.11.txt  > APRIL.messung0203.11a.txt

while true; do read str; if [ "$str" == "" ]; then break; fi; i=$[$i+1]; echo $str $(echo "N[3.54583 * (E^(-$i/269.674)) + 13.9883]" | math | grep Out | awk -F '= ' '{print $2}'); done < APRIL.messung0203.11.txt  > APRIL.messung0203.11b.txt

awk -f daylen.awk < messung.0203_breinigt > daylen.dat

mv daylen.dat daylen.dat_
awk '{if ($5 > 500) {print $1, $2, $3, $4, $5}}' < daylen.dat_ > daylen.dat

awk '{print $1, $5}' < daylen.dat > daylen.onlynum.dat