Water Pump Graph - BASH

#!/bin/bash
######################################################################
#Copyright (C) 2018  Kris Occhipinti
#https://filmsbykris.com

#This program is free software: you can redistribute it and/or modify
#it under the terms of the GNU General Public License as published by
#the Free Software Foundation, either version 3 of the License, or
#(at your option) any later version.

#This program is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#GNU General Public License for more details.

#You should have received a copy of the GNU General Public License
#along with this program.  If not, see <http://www.gnu.org/licenses/>.
######################################################################
tmp="/tmp/pump.dates"
log="log2.txt"

function main(){
  echo "-==Welcome==-"
  echo "Generating Data...."
  get_dates
  cat "$tmp"|sort -u|while read line
  do
    let count="$(cat "$tmp"|grep "$line"|wc -l)"
    printf "$line %03d:" $count
    for i in `seq 0 $count`;do
      echo -n "="
    done
    echo ""
  done
  exit 0
}

function get_dates(){
  cat $log|grep 20|cut -d\| -f1|while read d
  do
    date -d @$d +%Y-%m-%d;
  done > $tmp
}

main