in reply to DateCalc using Date::Manip

As others have noted, there are several ways to do calculations (exact, approximate, semi-approximate). Unfortunately, Date::Manip::DM6 (which is basically just an interface that is backward compatible with the older versions of Date::Manip) didn't currently support all of them (since they didn't even exist in older versions of Date::Manip).

The was no reason NOT to support them... I just had never thought to add them (and nobody had requested that). So I just did, and in the next version of Date::Manip, you'll be able to do: 

   my $dtopt= DateCalc($dt1,$dt2,'semi');

[download]

and get what you want. However, that won't work in the current version.

Getting what you want with the current version of Date::Manip::DM6 is harder because in the older module, there were only exact and approximate, and in newer versions there are exact, semi-approximate, and approximate, and it's challenging to get what you want. Really, the best way would be to do that calculation using the OO interface: 

use Date::Manip::Date;
my $date1 = new Date::Manip::Date;
my $date2 = $date1->new_date();
$date1->parse($dt1);
$date2->parse($dt2);
my $delt  = $date1->calc($date2,'semi');
my $delv  = $delt->value();
print "$delv\n";

[download]

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Re^2: DateCalc using Date::Manip
by huck (Prior) on Jan 10, 2017 at 18:03 UTC

    Wow, thanks

    But there still is a problem, that is semi-approx, and he wants semi-exact 

    use Date::Manip;
my $dt1="2016080100:00:00";
my $dt2='2016123100:00:00';
my $date1 = new Date::Manip::Date;
my $date2 = $date1->new_date();
$date1->parse($dt1);
$date2->parse($dt2);
my $delts  = $date1->calc($date2,'semi');
my $delte  = $date1->calc($date2,'exact');
my $delve=$delte->value();
my $delvs=$delts->value();

sub semi_exact { 
  my $delve=shift; 
  my @parts=split(':',$delve); 
  my $h0=$parts[4]+$parts[3]*24+$parts[2]*7*24; 
  my $w=sprintf('%d',$h0/(7*24)); 
  $h0=$h0-$w*7*24;
  if ($w<0) {$h0=$h0*-1;}
  my $d=sprintf('%d',$h0/24); 
  $h0=$h0-$d*24;
  my $delvse="0:0:$w:$d:$h0:$parts[5]:$parts[6]";
  return $delvse; 
} # semi-exact 

my $delvse=semi_exact($delve); 
print 'exact      :'.$delve."\n";
print 'semi-approx:'.$delvs."\n";
print 'semi-exact :'.$delvse."\n";


my $fe=DateCalc($dt1,$dt2,0); 
my $fse=semi_exact($fe); 
print 'functional semi-exact :'.$fse."\n";

exit;

    [download]
    output 
    exact      :0:0:0:0:3649:0:0
semi-approx:0:0:21:5:0:0:0
semi-exact :0:0:21:5:1:0:0
functional semi-exact :0:0:21:5:1:0:0

    [download]

[reply]
[d/l]
[select]

      I don't have a 'semi-exact' mode in Date::Manip... but what you're really saying is: convert an exact delta to a semi-approximate one.

      This is of course different from coming up with an semi-approximate delta from two dates (which is what I was doing... I should have noticed that it wasn't exactly what the OP was doing, but I got ahead of myself after noticing I couldn't use 'semi' mode in the older DateCalc).

      In any case, you can do the following: 

      use Date::Manip;
my $dt1='2016080100:00:00';
my $dt2='2016123100:00:00';
my $exact= DateCalc($dt1,$dt2);
my $semi = DateCalc($dt1,$dt2,'semi');
print "Exact      : $exact\n";
print "Semi       : $semi\n";
my $delta = ParseDateDelta($exact,'semi');
print "Exact->Semi: $delta\n";
print "\n";


use Date::Manip::Date;
my $date1 = new Date::Manip::Date;
my $date2 = $date1->new_date();
$date1->parse($dt1);
$date2->parse($dt2);
my $delt_x  = $date1->calc($date2);
my $delt_s  = $date1->calc($date2,'semi');
my $val     = $delt_x->value();
print "New Exact : $val\n";
$val        = $delt_s->value();
print "New Semi  : $val\n";
$delt_x->convert('semi');
$val        = $delt_x->value();
print "New Ex->Se: $val\n";

      [download]

      which yields: 

      Exact      : 0:0:0:0:3649:0:0
Semi       : 0:0:21:5:0:0:0
Exact->Semi: 0:0:21:5:1:0:0

New Exact : 0:0:0:0:3649:0:0
New Semi  : 0:0:21:5:0:0:0
New Ex->Se: 0:0:21:5:1:0:0

      [download]

      So you can see how to convert an exact delta to a semi-approximate one using either the old or new interfaces.

[reply]
[d/l]
[select]
      A BIG THANK YOU!!!!! I was able to sort out my problem with your code. Although, I need to make some modification to my code after it does the date calculation(with the code you have given) . I will keep you updated. MANY THANKS!!!!!!:)
[reply]

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