Extract data from OUTCAR to series XSF files as AENET training set (**Bash**)
===========

::

      #!/bin/sh
      #lipai@mail.ustc.edu.cn
      #generate xsf files using OUTCAR and POSCAR
      
      if [ $# = 0 ]; then
            out="OUTCAR"
      else
            out=$1
      fi
      echo $out
      rm *.temp
      
      # total number of ions in the system
      num_atom=`grep -m 1 "NIONS =" $out|awk '{print $12}'`
      echo "Total number of ions: $num_atom"
      
      # create temp files for writing xyz files
      typenum=`grep -m 1 'ions per type' $out |head -1 |awk '{print NF}' `
      typenum=$(($typenum-4)) # how many types of ions
      for i in `seq $typenum`
      do
                      elename=`grep -m $i POTCAR $out |tail -1 |awk '{print $3}'`
              j=$(($i+4))
              elenum=`grep -m 1 "ions per type" $out |awk -v j=$j '{print $j}'`
              echo $elename $elenum
              for j in `seq $elenum`
              do
                  echo $elename  >> type.temp
              done
      done
      grep -A 3 -m 1 "direct lattice vectors" $out \
      |tail -3 |awk '{printf("%f %f %f \n",$1,$2,$3)}' >primvec.temp
      grep "energy  without " $out |awk '{print $4}' >energy.temp
      awk '/POSITION/,/drift/{ if(NF==6) print $0 }' $out  > pos.temp
      
      lines=`wc pos.temp|awk '{print $1}'`
      num_str=`echo "$lines/$num_atom" |bc` # how many structures
      echo "Number of structures: $num_str"
      if [  -f all.xyz ]; then
          rm all.xyz
      fi
      
      for i in `seq $typenum`
      do
              elename=`grep -m $i POTCAR $out |tail -1 |awk '{print $3}'`
              j=$(($i+4))
              elenum=`grep -m 1 "ions per type" $out |awk -v j=$j '{print $j}'`
              echo $elename $elenum
              for j in `seq $elenum`
              do
                  echo $elename  >> type.temp
              done
      done
      
      echo "num of str: $num_str"
      
      for i in `seq $num_str`
      do
            energy=`head -n $i energy.temp|tail -1`
            echo "# total energy = $energy eV" >> str_$i.xsf
            echo " " >> str_$i.xsf
            echo "CRYSTAL" >> str_$i.xsf
            echo "PRIMVEC" >> str_$i.xsf
            cat primvec.temp >> str_$i.xsf
            echo "PRIMCOORD" >> str_$i.xsf
            echo "$num_atom 1" >> str_$i.xsf
            end=`echo "$i*$num_atom" |bc `
            head -n $end pos.temp|tail -n $num_atom >pos_i.temp
            paste type.temp pos_i.temp >> str_$i.xsf
            mv str_$i.xsf $out-$i.xsf
      done
      
      rm *.temp
      if [ ! -d "struc" ]; then
            mkdir struc
      fi
      mv *xsf struc