Shell Programming and Scripting

hi all,

i will like to modified some files with the extension .gjf . All this files have in first line this #P PM3 Opt and i want to change that to this :

Code:

 %nproc=2    
 %chk=filename.chk 
 #p B3LYP /6-31G** opt

in order to do that i have try to do a script with the sed command but i really don't know how to insert %nproc=2 in line N°1, %chk=filename.chk in line N°2 and #p B3LYP /6-31G** opt in line N°3 . The script that i have wrote is

Code:

 for x in $(ls *.gjf);  
   do n=$(echo $x | cut -d. -f1);
  echo " sed -i 's/#P PM3 Opt/nproc=2 %chk=$n.chk #p B3LYP \/6-31G** opt/g' $n.gjf" 
 
 done

but this change the text #P PM3 Opt by nproc=2 %chk=$n.chk #p B3LYP / 6-31G** opt all this text in the first line.

i will be very grateful if some one of the forum can help me in solve this problem.

thank you very much .

Code:

sed -i 's/#P PM3 Opt/nproc=2\n%chk=$n.chk\n#p B3LYP \/6-31G** opt/' *.gjf

New lines are \n in the code above

first i will like to thanks for the very quick answer that you provide me however i have change the scrip to this :

Code:

  for x in $(ls *.gjf);  
    do n=$(echo $x | cut -d. -f1); 
   echo "  sed -i 's/#P PM3 Opt/nproc=2\n%chk=$n.chk\n#p B3LYP \/6-31G** opt/g' $n.gjf  "
  done

but this script do not modified any file also in the second line i need the name of the file with this particular extension %chk=$n.chk

thank you very much.

Code:

#!/bin/sh

for x in *gjf; do
    n=${x%.*}
    sed -i0 's/#P PM3 Opt/nproc=2\n%chk='"$n"'.chk\n#p B3LYP \/6-31G** opt/' "$x"
done

Putting "$n" out of sed script seems to do the trick
[Wont edit this] I added 0 after -i in sed command so all gjf files will be backed up as .gjf0, in case something goes wrong

thank you very much for all the help, and again for the quick answer