Shell Programming and Scripting

x=0
MOLprev=0
while read line
do
    MOLcur=$(echo $line | awk '{print $5}')    
    if [[ "$MOLprev" -eq 9999 && "$MOLprev" -ne "$MOLcur" ]]
    then
        x=$((x+1))
        SCALE=$((x*10000))
    fi
    echo $line | awk -v var1=`echo $MOLprev` -v var2=`echo $SCALE` '{ 
        if (var1 -ge $5) 
            printf("%4s%7s%5s%4s%6s%12s%8s%8s\n",$1,$2,$3,$4,$5+var2,$6,$7,$8)
        else 
            printf("%4s%7s%5s%4s%6s%12s%8s%8s\n",$1,$2,$3,$4,$5,$6,$7,$8); 
        }'
    MOLprev=$MOLcur
done < atoms_done > $OUTPUT

awk '
# The BEGIN block gets run once, before any lines are read
BEGIN { x=0 MOLprev=0 }
# This block gets run once per line
{
  if ((MOLprev == 9999) && (MOLprev != $5))
  {
    x++;
    SCALE=x*10000;
  }

  if (MOLprev > $5) 
            printf("%4s%7s%5s%4s%6s%12s%8s%8s\n",$1,$2,$3,$4,$5+SCALE,$6,$7,$8)
  else 
            printf("%4s%7s%5s%4s%6s%12s%8s%8s\n",$1,$2,$3,$4,$5,$6,$7,$8); 

  MOLprev=MOLcur;
}' < inputfile > outputfile

#!/usr/bin/ksh
typeset -i mPrev=7777
typeset -i mCurr=-1
while read mFld1 mFld2 mFld3 mFld4 mFld5 mOther
do
  if [[ ${mFld5} -ne ${mPrev} ]]; then
    mCurr=${mCurr}+1
  fi
  echo ${mFld1} ${mFld2} ${mFld3} ${mFld4} ${mCurr} ${mOther}
  mPrev=${mFld5}
done < input_file

mCurr=${mCurr}+1

((mCurr+=1))

#!/bin/ksh

integer limit=100000
integer ctr=0

function method1 {
ctr=0
print "\nfunction 1 starting $ctr"
while ((ctr < $limit))
do
   ctr=${ctr}+1
done
print "function 1 ending $ctr"
}

function method2 {
ctr=0
print "\nfunction 2 starting $ctr"
while ((ctr < $limit))
do
  ((ctr+=1))
done
print "function 2 ending $ctr"
}

time method1

time method2

exit 0

 $ ./aa

function 1 starting 0
function 1 ending 100000

real    0m3.46s
user    0m3.45s
sys     0m0.00s

function 2 starting 0
function 2 ending 100000

real    0m2.16s
user    0m2.16s
sys     0m0.00s
  $

awk '
# The BEGIN block gets run once, before any lines are read
BEGIN { x=0; MOLprev=0; }
# This block gets run once per line
{

  if ((MOLprev == 9999) && (MOLprev != $5))
  {
    x++;
    SCALE=x*10000;
  }

  if (MOLprev -ge $5)
            printf("%4s%7s%5s%4s%6s%12s%8s%8s\n",$1,$2,$3,$4,$5+SCALE,$6,$7,$8)
  else 
            printf("%4s%7s%5s%4s%6s%12s%8s%8s\n",$1,$2,$3,$4,$5,$6,$7,$8); 
            
  MOLprev=$5;
}' < atoms_done > $OUTPUT