Shell Programming and Scripting

# $1 is pos file and $2 is input file

# column positions are read into pos_array
index=0
newfile="outfile"
> $newfile
while read line;
do
pos_array[$index]="$line"
index=$(($index+1))
done < $1

# read each line, find substring
while read line1;
do
i=0
while [ $i -lt $index ]
do
string=(${pos_array[i]})
pos1=${string[0]}
pos2=${string[1]}
pos1=$(($pos1-1))
pos2=$(($pos2-$pos1)) #no of columns
field=${line1:$pos1:$pos2}
#echo "field is $field"
tmpfield=`echo "$field" | sed -e 's/^\([0-9.]*\)\(-*\)\( *$\)/\2\1\3/;'`
#echo "tmpfield is $tmpfield"


echo -n "$tmpfield" >> $newfile
i=$(($i+1))
done
echo >> $newfile
done < $2