#!/bin/bash
# Takes data file with:
# Day Month Year timeofday val1 val2 ... valn
# outputs:
# Day Month Year timeofday val(column_number) normalized_column_value

# useage: normalize column_number file_name

# find number of values on the line
linelen=`head -1 <$2 | dm N`

# check for valid column value
if [ $1 -le $linelen ]
then

  # determine number of years of data for file
  firstyr=`head -1 < $2 | dm x3`
  lastyr=`tail -2 < $2 | dm x3 | stats max`
  let totyr=lastyr-firstyr+1

  # set up initial lastval array
  for nline in $(seq $linelen)
  do
    lastval[nline]=0
  done

  # set first day, first month and first year values as well
  lastval[1]=`head -1 < $2 | dm x1`
  lastval[2]=`head -1 < $2 | dm x2`
  lastval[3]=$firstyr

  # grab entire file into memory
  nline=0
  for singval in ${lineval[@]}
  do
    let nline=nline+1
    lastval[nline]=${nextval[nline]}
    nextval[nline]=$singval
    if [ $nline -eq $linelen ]
    then
      # same day?
      if [ nextval[1] -eq lastval[1] ]
      then
        # same day
        
      else
        # new day

      fi
    fi
    nline=0
  done

else
    echo "Column number $1 does not exist in the file."
fi