Find First Date of A Calendar Month\Year

[idgarad]

Very simple in description but tricky to implement so far. What I am
after is given a year, say 2006, what is the First sunday's date on the
calendar (For January). For instance in 2006 this would be january 1st
2006. But in 2005 it would be Dec 26th 2004. Is there a simple module
for getting this kind of date?

Ken

 

[Paul Lalli]

Very simple in description but tricky to implement so far. What I am
after is given a year, say 2006, what is the First sunday's date on the
calendar (For January). For instance in 2006 this would be january 1st
2006. But in 2005 it would be Dec 26th 2004. Is there a simple module
for getting this kind of date?

I'm sure one of the hundreds of Date* modules available on CPAN can do
this, but if you don't feel like installing a non-standard module just
for this purpose, this seems to work for me:

#!/usr/bin/perl
use strict;
use warnings;
use POSIX qw/strftime/;
use Time::Local;

for my $y (2004, 2005, 2006) {
my $first = first_sunday($y);
print "$y: ", strftime("%C", localtime($first)), "\n";
}

sub first_sunday {
my $y = shift;
my $dow = strftime("%w", 0,0,0,1,0,$y-1900);
my $time = timelocal(0,0,0,1,0,$y-1900);
return $time - ($dow * 24 * 60 * 60);
}
__END__
2004: Sun Dec 28 00:00:00 EST 2003
2005: Sun Dec 26 00:00:00 EST 2004
2006: Sun Jan 1 00:00:00 EST 2006

Basically, find the day of the week of the first of the year (as an
integer from 0 - 6). Then take that date, and subtract that number of
days from it.

Paul Lalli

 

[Tad McClellan]

Very simple in description but tricky to implement so far. What I am
after is given a year, say 2006, what is the First sunday's date on the
calendar (For January). For instance in 2006 this would be january 1st
2006. But in 2005 it would be Dec 26th 2004. Is there a simple module
for getting this kind of date?

-----------------------------
#!/usr/bin/perl
use warnings;
use strict;
use Date::Calc qw/ Nth_Weekday_of_Month_Year /;

my $year = 2006;
my $first_Sunday = sprintf '%4d-%02d-%02d',
Nth_Weekday_of_Month_Year($year,1,7,1);

print "the first Sunday of $year is $first_Sunday\n";

 

[anno4000]

Very simple in description but tricky to implement so far. What I am
after is given a year, say 2006, what is the First sunday's date on the
calendar (For January). For instance in 2006 this would be january 1st
2006. But in 2005 it would be Dec 26th 2004. Is there a simple module
for getting this kind of date?

Just one question: How is Dec 26th 2004 the first Sunday in 2005?

Anno

 

[usenet]

Just one question: How is Dec 26th 2004 the first Sunday in 2005?

I think the OP means if you look at a calendar (where Sunday is the
first column) and see which row holds Jan 1, what is the date of the
first column of that row?

 

[usenet]

But in 2005 it would be Dec 26th 2004. Is there a simple module
for getting this kind of date?

Date::Calc's perldocs show several examples which could be adapted,
notably:

7) How do I calculate the date of the Wednesday of the same week as the
current date?

10) How do I calculate the last and the next Saturday for any given
date?

 

[Idgarad]

The solution worked great but I modified it to take a month parameter
to ease the consecutive use of generating the calendars following
January. i.e. first_sunday_of_calmonth(1,2005) and
first_sunday_of_calmonth(4,2006).

sub first_sunday_of_calmonth {
my $m = shift;
my $y = shift;

my $dow = strftime("%w", 0,0,0,1,$m-1,$y-1900);
my $time = timelocal(0,0,0,1,$m-1,$y-1900);
return $time - ($dow * 24 * 60 * 60);
}

A latter poster was correct, I was seeking the upper left-most box on a
calendar. I have posted below the finished product which was a simple
pager rotation script that generates a calendar in Excel format. It is
designed at this time only to handle 3 people as I have to fix the mod
(%) math to handle a variable number of people properly. If anyone
knows a good solution please let me know. Critiques welcome!

--schedule.pl--
#!/usr/bin/perl
###### List of People to be on rotation
# --users, -u = "jeff,john,jack" with the person working evening that
week covering the weekend
# --year, -y = "2008" for instance.
# You may need to set yout TZ environment variable if the script cannot
# determine your time zone from the system.
######
use Getopt::Long;
use Date::Manip;
use Spreadsheet::WriteExcel;
use Calendar::Functions;
use Date::Holidays::USFederal;

use POSIX qw/strftime/;
use Time::Local;

my @users = ();

$result = GetOptions ("users|u=s" => \@users,
"year|y=s" => \$year);




print "first sunday of week 1 is: ", ParseDate("sunday week 0
$year"),"\n";
@users = split(/,/,join(',',@users));
print @users;
#this would be used later in mod math to get things rotating properly
#but it fails miserable due to the addition later
$totalUsers=scalar(@users);

my $first = first_sunday_of_calmonth(1,$year);
$date=strftime("%m/%d/%Y", localtime($first));

print ("Initial Offset is $date\n");


#Make A SpreadSheet
my $workbook = Spreadsheet::WriteExcel->new("alpha-pager-$year.xls"); #
Step 1


#Build Formats

$fmtMonth=$workbook->add_format();
$fmtMonth->set_align('center');
$fmtMonth->set_align('Vcenter');
$fmtMonth->set_border(1);
$fmtMonth->set_bg_color('white');
$fmtMonth->set_font('Times New Roman');
$fmtMonth->set_size(24);
$fmtMonth->set_bold(1);

$fmtWeek=$workbook->add_format();
$fmtWeek->set_align('center');
$fmtWeek->set_align('Vcenter');
$fmtWeek->set_border(1);
$fmtWeek->set_bg_color('white');
$fmtWeek->set_font('Times New Roman');
$fmtWeek->set_size(14);
$fmtWeek->set_bold(1);

$fmtDate=$workbook->add_format();
$fmtDate->set_align('left');
$fmtDate->set_align('top');
$fmtDate->set_left(1);
$fmtDate->set_right(1);
$fmtDate->set_bg_color('white');
$fmtDate->set_font('Times New Roman');
$fmtDate->set_size(12);
$fmtDate->set_bold(1);

$fmtText=$workbook->add_format();
$fmtText->set_align('left');
$fmtText->set_align('top');
$fmtText->set_left(1);
$fmtText->set_right(1);
$fmtText->set_bg_color('white');
$fmtText->set_font('Arial');
$fmtText->set_size(10);
$fmtText->set_bold(0);

$fmtHoliday=$workbook->add_format();
$fmtHoliday->set_align('right');
$fmtHoliday->set_align('bottom');
$fmtHoliday->set_text_wrap(1);
$fmtHoliday->set_left(1);
$fmtHoliday->set_right(1);
$fmtHoliday->set_bottom(1);
$fmtHoliday->set_bg_color('white');
$fmtHoliday->set_font('Arial');
$fmtHoliday->set_color('Blue');
$fmtHoliday->set_size(8);
$fmtHoliday->set_bold(1);

$fmtDate2=$workbook->add_format();
$fmtDate2->set_align('left');
$fmtDate2->set_align('top');
$fmtDate2->set_left(1);
$fmtDate2->set_right(1);
$fmtDate2->set_bg_color('silver');
$fmtDate2->set_font('Times New Roman');
$fmtDate2->set_color('grey');
$fmtDate2->set_size(12);
$fmtDate2->set_bold(1);

$fmtText2=$workbook->add_format();
$fmtText2->set_align('left');
$fmtText2->set_align('top');
$fmtText2->set_left(1);
$fmtText2->set_right(1);
$fmtText2->set_bg_color('silver');
$fmtText2->set_font('Arial');
$fmtText2->set_color('grey');
$fmtText2->set_size(10);
$fmtText2->set_bold(0);

$fmtHoliday2=$workbook->add_format();
$fmtHoliday2->set_align('right');
$fmtHoliday2->set_align('bottom');
$fmtHoliday2->set_left(1);
$fmtHoliday2->set_right(1);
$fmtHoliday2->set_bottom(1);
$fmtHoliday2->set_bg_color('silver');
$fmtHoliday2->set_font('Arial');
$fmtHoliday2->set_color('plum');
$fmtHoliday2->set_size(8);
$fmtHoliday2->set_text_wrap(1);
$fmtHoliday2->set_bold(1);

@week=(
UnixDate(DateCalc($date,"+0 days"),"%A"),
UnixDate(DateCalc($date,"+1 days"),"%A"),
UnixDate(DateCalc($date,"+2 days"),"%A"),
UnixDate(DateCalc($date,"+3 days"),"%A"),
UnixDate(DateCalc($date,"+4 days"),"%A"),
UnixDate(DateCalc($date,"+5 days"),"%A"),
UnixDate(DateCalc($date,"+6 days"),"%A"),
);




for($month=1;$month<13;$month++)
{

$first = first_sunday_of_calmonth($month,$year);
$date=strftime("%m/%d/%Y", localtime($first));

$workbook->add_worksheet((UnixDate("$month/1/$year","%B")));

$workbook->sheets($month-1)->merge_range(0,0,0,6,UnixDate("$month/1/$year","%B")."
- $year",$fmtMonth);

$workbook->sheets($month-1)->set_column('A:A', 15);
$workbook->sheets($month-1)->set_column('B:B', 15);
$workbook->sheets($month-1)->set_column('C:C', 15);
$workbook->sheets($month-1)->set_column('D', 15);
$workbook->sheets($month-1)->set_column('E:E', 15);
$workbook->sheets($month-1)->set_column('F:F', 15);
$workbook->sheets($month-1)->set_column('G:G', 15);

for($dow=0;$dow<7;$dow++){

$workbook->sheets($month-1)->write(1,$dow,dotw($dow),$fmtWeek);
}
#Render the Calendar Entries

for($row=2;$row < 30;$row+=5)
{

for($cols=0;$cols<7;$cols++)
{

#define the Roles, this is where mod math does
if not just three
$sunday=$users[($row)%$totalUsers];
$saturday=$users[($row+2)%$totalUsers];
$weekday=$users[($row+1)%$totalUsers];
$weeknight=$users[($row+2)%$totalUsers];

if (UnixDate($date,"%m") == $month) {


$workbook->sheets($month-1)->write($row,$cols,UnixDate($date,"%d"),$fmtDate);

$workbook->sheets($month-1)->write_blank($row+1,$cols,$fmtDate);
SWITCH: {

$cols==0 and do {

$workbook->sheets($month-1)->write($row+2,$cols,"Primary:
$sunday",$fmtText);

$workbook->sheets($month-1)->write_blank($row+3,$cols,$fmtText);

$workbook->sheets($month-1)->write($row+4,$cols,holidayCheck($date),$fmtHoliday);
last;
};

$cols==6 and do {

$workbook->sheets($month-1)->write($row+2,$cols,"Primary:
$saturday",$fmtText);

$workbook->sheets($month-1)->write_blank($row+3,$cols,$fmtText);

$workbook->sheets($month-1)->write($row+4,$cols,holidayCheck($date),$fmtHoliday);
last;
};
$cols!=6 || $cols!=0 and do {

$workbook->sheets($month-1)->write($row+2,$cols,"Days:
$weekday",$fmtText);

$workbook->sheets($month-1)->write($row+3,$cols,"Evenings:
$weeknight",$fmtText);

$workbook->sheets($month-1)->write($row+4,$cols,holidayCheck($date),$fmtHoliday);
last;
}

} #END OF SWITCH
} else {

$workbook->sheets($month-1)->write($row,$cols,UnixDate($date,"%d"),$fmtDate2);

$workbook->sheets($month-1)->write_blank($row+1,$cols,$fmtDate2);
SWITCH: {

$cols==0 and do {

$workbook->sheets($month-1)->write($row+2,$cols,"Primary:
$sunday",$fmtText2);

$workbook->sheets($month-1)->write_blank($row+3,$cols,$fmtText2);

$workbook->sheets($month-1)->write($row+4,$cols,holidayCheck($date),$fmtHoliday2);
last;
};

$cols==6 and do {

$workbook->sheets($month-1)->write($row+2,$cols,"Primary:
$saturday",$fmtText2);

$workbook->sheets($month-1)->write_blank($row+3,$cols,$fmtText2);

$workbook->sheets($month-1)->write($row+4,$cols,holidayCheck($date),$fmtHoliday2);
last;
};
$cols!=6 || $cols!=0 and do {

$workbook->sheets($month-1)->write($row+2,$cols,"Days:
$weekday",$fmtText2);

$workbook->sheets($month-1)->write($row+3,$cols,"Evenings:
$weeknight",$fmtText2);

$workbook->sheets($month-1)->write($row+4,$cols,holidayCheck($date),$fmtHoliday2);
last;
}

} #END OF SWITCH


}
$date=DateCalc($date,"+1 day");


}

if(UnixDate($date,"%m") > $month) {last;}
};

#Set Up The Printer Settings
$workbook->sheets($month-1)->center_horizontally();
$workbook->sheets($month-1)->center_vertically();
$workbook->sheets($month-1)->set_paper(1);
$workbook->sheets($month-1)->set_margins(.6);
$workbook->sheets($month-1)->set_landscape();

$workbook->sheets($month-1)->print_area(0,0,$row+4, $cols-1)

}
$workbook->close();

sub holidayCheck {
my $t = shift;
my $y = UnixDate($t,"%Y");
my $m = UnixDate($t,"%m");
my $d = UnixDate($t,"%d");

my $checkDate = "$m/$d/$y";

print "My CheckDate= $checkDate\n";

SWITCH: {

$checkDate eq "01/02/$y" and do {return "New Year's Day";};
$checkDate eq "01/16/$y" and do {return "Martin Luther King, Jr.
Day";};
$checkDate eq "02/20/$y" and do {return "Presidents' Day";};
$checkDate eq "05/29/$y" and do {return "Memorial Day";};
$checkDate eq "07/04/$y" and do {return "Independence Day";};
$checkDate eq "09/04/$y" and do {return "Labor Day";};
$checkDate eq "10/09/$y" and do {return "Columbus Day";};
$checkDate eq "11/11/$y" and do {return "Veterans' Day";};
$checkDate eq "11/23/$y" and do {return "Thanksgiving Day";};
$checkDate eq "12/25/$y" and do {return "Christmas Day";};

} #END SELECT


}

sub first_sunday_of_calmonth {
my $m = shift;
my $y = shift;

my $dow = strftime("%w", 0,0,0,1,$m-1,$y-1900);
my $time = timelocal(0,0,0,1,$m-1,$y-1900);
return $time - ($dow * 24 * 60 * 60);
}

--End Schedule--

 

[Idgarad]

Dead right David, that is what I was after. Effectivly what is the date
in row 0, col 0 of the calendar. I posted the completed work. Thank you
all for the help.