I'm using DateManip for ParseDate and UnixDate. I'm not finding a routine to do this. Are you using ParseRecur? -Travis

Once again we use day 0-6. I have added a hash to show the output in a nice format. Oh you can do it in a one liner as shown :-). The advantage of 0-6 for the days is that we can use modulus to good effect to generate our 7 indexes (0-6) for the days. You could always copy element 0 of the day count array to element 7 if you are really set on having Sunday as day 7 or add 1 to the mod and iterate from ($firstday-1)..($days+$firstday-2) but you do waste element 0 in your array.

my $days = 71;
my $firstday = 5;
my @daycounts = (0) x 7; # initialise 7 array elements to 0

for my $day_num( $firstday .. ($days+$firstday-1) ) {
    $daycounts[$day_num%7]++;
}

# now print it out nice and pretty

my %weekdays = (
    1 => Monday,
    2 => Tuesday,
    3 => Wednesday,
    4 => Thursday,
    5 => Friday,
    6 => Saturday,
    0 => Sunday);

for my $day_num(0..6) {
    print "$daycounts[$day_num]\t$weekdays{$day_num}\n";
}

# here it is as a one liner
$daycounts[$_%7]++ for $firstday..($days+$firstday-1);
[download]

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In this, I am getting the answer I expect. As I said before, I'm using Date::Manip, which is why I'm using 1..7. But I can +/- 1 as necessary, though I do need to make Monday 0 and Sunday 6. I like the one liner, since this is going to be put into an ASP, that helps.

Though you solution does require it step through the date range. That can be annoying for very large date ranges.

-Travis

$daycounts[($firstday+$_-1)%7] = int(($days+6-$_)/7) for(0..6);
[download]

                - Ant

This works very well. It doesn't require a lop larger than 7. But I take out the -1 to get

$daycounts[($firstday+$_)%7] = int(($days+6-$_)/7) for(0..6);
[download]

And get an array where Monday is 0 and Sunday is 6. This way I can use the UnixDate result -1 to match it to this result.

-Travis

I put the -1 in because you said $firstday went from 1-7, was I wrong?

                - Ant

use strict;

# Days start at 0, just like arrays
my $start_day = 6;
my $days = 7;
my @cnts = daycounts($start_day, $days);
for (0..6) {
 print "$_: $cnts[$_]\n";
}
sub daycounts {
 use integer;
 my $start_day = shift;
 my $days = shift;
 my $end_day = ($start_day + $days) % 7;
 my $compare = ($start_day <= $end_day)
  ? sub { my $num = shift; $start_day <= $num and $num <= $end_day }
  : sub { my $num = shift; $num <= $end_day or $start_day <= $num };
 my @adjust = map { $compare->($_)? 1 : 0 } 0..6;
 my $cnts = $days / 7;
 map { $cnts + $adjust[$_] } 0..6;
}
[download]

Another update: Re:ThuG's reply - I made the assumption that zero days means just the start day, and 1 day means the start day and the next day, so 17 days from Wednesday would take you to Saturday, not Friday. So just subtract one from $days coming in to get what you expect.

I'm using 1..7 because Date::Manip returns 1 for the first day of the week, not 0. Yes, I loose the 0 index. That isn't a problem since I can very easily add or subtract 1 as needed to convert between Date::Manip and this code.

When I step through your code, which by the way, took some work for me since you are using much Perl mojo that I'm just not used to using, I am not getting the answer I expect.

If you start on Wednesday ($start_day = 2) and run to the third Friday ($days = 17), then you should have two Mondays, Tuesdays, Saturdays, and Sundays, and three Wednesdays, Thrusdays, and Fridays. I expect 2, 2, 3, 3, 3, 2, 2, but I get 2, 2, 3, 3, 3, 3, 2.

-Travis

Here is an update that does exactly as you ask (Monday = 1 and Sunday = 7) and iterates a maximum of 6 times - ie it adds initialises the array with int($days/7) and just adds the remaining 0-6 to the appropriate elements. This is as fast and efficient as it gets.

my $days = 72;
my $firstday = 5;
# for each 7 days each element gets a value of +1
# initialise 8 array elements
my @daycounts = (int($days/7)) x 8; 
$days = $days%7;

for my $day_num( ($firstday-1) .. ($days+$firstday-2) ) {
    $daycounts[1+$day_num%7]++;
}

# now print it out nice and pretty

my %weekdays = (
    1 => Monday,
    2 => Tuesday,
    3 => Wednesday,
    4 => Thursday,
    5 => Friday,
    6 => Saturday,
    7 => Sunday);

for my $day_num(1..7) {
    print "$daycounts[$day_num]\t$weekdays{$day_num}\n";
}

# here it is as a one liner
$daycounts[1+$_%7]++ for ($firstday-1)..($days+$firstday-2);
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

Scott