Hi experts, I have created my own program to add and subtract (in this example Im subtraction 7 days from current day so basically a week ago) calendar dates. Is there an easier way to do this without having to update the code (in my validate_years and validate_month subs). It works but Im still unconfident about the outcome. Sorry the code is so long. Any advice would be appreciated. Thanks in advance... Fue 
#!/usr/bin/perl

#Variables for dates
$year = qx(date +%Y);
$month = qx(date +%b);
$date = qx(date +%d);
$date2 = $date;
$month = uc($month);
chop($month);
chop($date);
chop($date2);
chop($year);

#Opens template and write to SAS file to use
die("Cannot open daily_pull_temp.sas to write to.")
     unless(open(WRITE, ">daily_pull_temp.sas"));
 
die("Cannot open daily_pull.sas to read from.")
     unless(open(GETDATA, "<daily_pull.sas"));
while($get = <GETDATA>) {
    if ($get =~ /<date2>/) {
        $get =~ s/<date2>/$date2/g;
    }
     if ($get =~ /<year><month>/) {
        if ($date <= 7) {
            $month = &minus_month($month);
               $newdate = &validate_Month($month);
            $date = ($newdate + $date); 
            $date = $date - 7;
#             $year = &validate_Year($month);
            $month = &change_mo2num($month);
            $get =~ s/<year>/$year/g;
            $get =~ s/<month>/$month/g;
            $get =~ s/<date>/$date/g;
            print WRITE "$get";
          } 
          else {
               #month stays as current month
               $newdate = &validate_Month($month);
#                $year = &validate_Year($month);
               $month = &change_mo2num($month);
            $date = $date - 7;
            if ($date < 10) {
                $date = "0" . $date;
            }
               $get =~ s/<year>/$year/g;
            $get =~ s/<month>/$month/g;
            $get =~ s/<date>/$date/g;
            print WRITE "$get";
          }
     }
    else {    
        print WRITE "$get";
    }
}
close(WRITE);
close(GETDATA);

###### SUBS START HERE ###############

sub validate_Year {
    my ($month) = @_;
    if ($month eq "jan") {
          $yr = qx(date +%Y);
          return $yr;
     }
     else {
          ####### Must Change #######
          $yr = "2003";
     }
}
 

sub validate_Month {
    my ($m) = @_;
     if (($m eq "JAN") xor($m eq "MAR") xor ($m eq "MAY") xor
     ($m eq "JUL") xor ($m eq "AUG") xor ($m eq "OCT") xor
     ($m eq "DEC")) {
           $day = 31;
           return $day;
     }
     elsif (($m eq "APR") xor($m eq "JUN") xor ($m eq "SEP") xor
     ($m eq "NOV")) {
          $day = 30;
          return $day; 
     }
     elsif ($m = "FEB") {
         if (($testyear eq "2003") xor ($testyear eq "2005") xor ($tes
+tyear eq "2007")
          xor ($testyear eq "2009")) {
               $day = 28;
               return $day;
          }
          else {
               $day = 29;
               return $day;
          }
     }
}
 
 
 
sub add_month {
    my ($month) = @_;
    if ($month eq "JAN") {
          $month = "FEB";
          return $month;
     }
     elsif ($month eq "FEB") { 
          $month = "MAR";
          return $month;
     }
     elsif ($month eq "MAR") { 
          $month = "APR";
          return $month;
     }
     elsif ($month eq "APR") {
          $month = "MAY";
          return $month;
     }
     elsif ($month eq "MAY") {
          $month = "JUN";
          return $month;
     }
     elsif ($month eq "JUN") {
          $month = "JUL";
          return $month;
     }
     elsif ($month eq "JUL") {  
          $month = "AUG";

          return $month;
     }
     elsif ($month eq "AUG") { 
          $month = "SEP";
          return $month;
     }
     elsif ($month eq "SEP") {
          $month = "OCT";
          return $month;
     }
     elsif ($month eq "OCT") {
          $month = "NOV";
          return $month;
     }
     elsif ($month eq "NOV") {
          $month = "DEC";
          return $month;
     }
     elsif ($month eq "DEC") {
          $month = "JAN";
          return $month;
     }
}


sub minus_month {
    my ($month) = @_;
     if ($month eq "JAN") {
          $month = "DEC";
          return $month;
     }
     elsif ($month eq "FEB") { 
          $month = "JAN";
          return $month;
     }
     elsif ($month eq "MAR") { 
          $month = "FEB";
          return $month;
     }
     elsif ($month eq "APR") {
          $month = "MAR";
          return $month;
     }
     elsif ($month eq "MAY") {
          $month = "APR";
          return $month;
     }
     elsif ($month eq "JUN") {
          $month = "MAY";
          return $month;
     }
     elsif ($month eq "JUL") {  
          $month = "JUN";
          return $month;
     }
     elsif ($month eq "AUG") { 
          $month = "JUL";
          return $month;
     }
     elsif ($month eq "SEP") {
          $month = "AUG";
          return $month;
     }
     elsif ($month eq "OCT") {
          $month = "SEP";
          return $month;
     }
     elsif ($month eq "NOV") {
          $month = "OCT";
          return $month;
     }
     elsif ($month eq "DEC") {
          $month = "NOV";
          return $month;
     }
}
 
#The 2 subroutines for date conversion
sub change_num2mo{
    my ($month) = @_;
    if ($month =~ /01/) {
          $num_month = "jan";
          return $num_month;
     }
     if ($month =~ /02/) {
          $num_month = "feb";
          return $num_month;
     }
     if ($month =~ /03/) {
          $num_month = "mar";
          return $num_month;
     }
     if ($month =~ /04/) {
          $num_month = "apr";
          return $num_month;
     }
     if ($month =~ /05/) {
          $num_month = "may";
          return $num_month;
     }
     if ($month =~ /06/) {
          $num_month = "jun";
          return $num_month;
     }
     if ($month =~ /07/) {
          $num_month = "jul";
          return $num_month;
     }
     if ($month =~ /08/) {
          $num_month = "aug";
          return $num_month;
     }
     if ($month =~ /09/) {
          $num_month = "sep";
          return $num_month;
     }
     if ($month =~ /10/) {
          $num_month = "oct";
          return $num_month;
     }
     if ($month =~ /11/) {
          $num_month = "nov";
          return $num_month;
     }
     if ($month =~ /12/) {
          $num_month = "dec";
          return $num_month;
     }
}

sub change_mo2num {
    my ($month) = @_;
     if ($month =~ /JAN/) {
          $num_month = "01";
          return $num_month;
     }
     if ($month =~ /FEB/) {
          $num_month = "02";
          return $num_month;
     }
     if ($month =~ /MAR/) {
          $num_month = "03";
          return $num_month;
     }
     if ($month =~ /APR/) {
          $num_month = "04";
          return $num_month;
     }
     if ($month =~ /MAY/) {
          $num_month = "05";
          return $num_month;
     }
     if ($month =~ /JUN/) {
          $num_month = "06";
          return $num_month;
     }
     if ($month =~ /JUL/) {
          $num_month = "07";
          return $num_month;
     }
     if ($month =~ /AUG/) {
          $num_month = "08";
          return $num_month;
     }
     if ($month =~ /SEP/) {
          $num_month = "09";
          return $num_month;
     }
     if ($month =~ /OCT/) {
          $num_month = "10";
          return $num_month;
     }
     if ($month =~ /NOV/) {
          $num_month = "11";
          return $num_month;
     }
     if ($month =~ /DEC/) {
          $num_month = "12";
          return $num_month;
     }
}

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In reply to adding/subtracting calender dates by Fuism

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