sub conv2jul {
   my $moda=shift;
   my @Days = (0,31,28,31,30,31,30,31,31,30,31,30,31);
   if ($leapyear) { $Days [2] = 29; }
   my $jul = 0;  my $i = 0;
   my $mo = substr($moda,0,2);
   my $da = substr($moda,2,2);
   if (($mo <= 0) || ($mo > 12)) { return "000"; }
   if (($da <= 0) || ($da > 31)) { return "000"; }
   for ($i = 0;$i < $mo;$i++) { $jul += $Days[$i]; }
   $jul += $da;
   return $jul;
}