Input:
$str="Thu Mar 25 01:48:45 IST 2011";
Desired output:
2011-03-25
I want only date, not the time.
#!/usr/bin/env perl
use strict;
use warnings;
use Time::Piece;
my $tstamp = Time::Piece->strptime
("Thu Mar 25 01:48:45 2011", "%a %b %d %H:%M:%S %Y");
print $tstamp->strftime("%Y-%m-%d\n");
use Date::Manip;
$str =~ s/[[:upper:]]{3}//; # Remove timezone
$d = ParseDate($str);
die "Invalid date\n" unless $d;
$d=~s/(....)(..)(..).*/$1-$2-$3/;
print "$d\n";
Heck, if you know the format of the date, you don't even need to use a Perl module to manipulate the date and time:
my %months = (Jan => 1, Feb => 2, Mar => 3, Apr => 4 ...);
my $st r= "Thu Mar 25 01:48:45 IST 2011";
$st =~! /\S+\s+(\S+)\s+(\S+)\s+\S+\s+\S+(\S+)/;
my $date = sprintf "%s-%02s-%02s", $3, $months{$1}, $2;
Okay, this is very error prone, and you probably want to do a lot of error checking. The regular expression I used could be formatted a bit stronger (checking for characters and numbers instead of just "not white space". And, you probably want to make sure the month is valid too.
Actually, you're better off using a Date/Time module to do this. I was going to recommend Time::Piece, but James_R_Ferguson beat me to it.
Related
I am running into issues converting the date Apr 9 2017 3:45:00:000AM to 2017-04-09 03:45:00
Here's what i have tried.
use DateTime::Format::Strptime;
my $strp = DateTime::Format::Strptime->new(pattern => '%h %d %Y %H:%M',);
$start_date = $strp->parse_datetime('Apr 9 2017 3:45:00:000AM');
prints 2017-04-09T03:45:00 and not 2017-04-09 03:45:00. Trying to get 24 hour clock so when i switch AM to PM the same time prints.
Update See end for an strptime pattern to parse the shown input string format correctly
What is shown works,† and so the DateTime::Format::Strptime constructor returns a DateTime object. But when an object is simply printed then one gets the stringification that is shown.
So you need to format it for printing as desired. A general way is with strftime
say $start_date->strftime("%F %T");
where both %F and %T are shorthands, see strftime patterns
Or combine the basic ymd and hms methods
say $start_date->ymd('-') . ' ' . $start_date->hms(':');
See the docs and adjust if/as needed. I didn't understand some details.
† It works only by accident in this exact example, since the pattern given to use for parsing in new is wrong for the shown input format, and is also inconsistent with stated requirements
The shown pattern doesn't have a format specifier for the seconds, nor for the milliseconds that follow it, nor for the following AM/PM -- all expected in the input string. So in general an input in the shown form cannot be parsed correctly with the shown pattern
The %H matches 00-23 hour, so not 12-hour clock which is stated as expected and is implicit by the presence of AM. (It still matches a 12-hour-time number but it won't once the missing AM/PM format specifier is added.)
The pattern in the OP works and parses the given input correctly because 03:45... happens to be in AM, and the module uses regex to match the given pattern anywhere in the given string (by default), so %H:%M matches 03:45 and the rest of the input string doesn't matter. If we turn on strict in the constructor this'll fail. See documentation.
Assuming that the shown input is the correct part we'd need
my $strp = DateTime::Format::Strptime->new(
pattern => '%h %d %Y %I:%M:%S%3N%p'
);
Here %I is for 12-hour clock (1-12), added %S is for seconds and %3N for milliseconds (see the page in docs for patterns, linked above), and %p for AM/PM.
The rest then works as it stands, along with printing in a desired format given above.
Following code demonstrates how desired output can be achieved without any modules
use strict;
use warnings;
use feature 'say';
my $date = 'Apr 9 2017 3:45:00:000AM';
my #fields = qw/month mday year hour min sec usec/;
my %months = ( Jan => 1, Feb => 2, Mar => 3,
Apr => 4, May => 5, Jun => 6,
Jul => 7, Aug => 8, Sep => 9,
Oct => 10, Nov => 11, Dec => 12
);
my %parts;
#parts{#fields} = split "[ :]+", $date;
$parts{hour} += 12 if $parts{usec} =~ /PM/;
$parts{month} = $months{ $parts{month} };
printf "%04d-%02d-%02d %02d:%02d:%02d\n",
#parts{qw/year month mday hour min sec/};
Perl code with assistance of module
use strict;
use warnings;
use feature 'say';
use DateTime::Format::DateParse;
my($date, $dt);
$date = 'Apr 9 2017 3:45:00:000AM';
$date =~ s/:(\d{3}[AP]M)/.$1/;
$dt = DateTime::Format::DateParse->parse_datetime( $date );
$date = $dt;
$date =~ s/T/ /;
say $date;
There are two issues with your code. First, the pattern you use to parse your date is not correct: %H is used for a 24-hour format hour. Instead, you should use a combination of %i (12-hour) and %p (AM/PM). Second, to print a DateTime object, you should first format it first (using ->strftime or ->ymd() for instance).
The milliseconds in the date are, however, a bit of an issue because strptime does not have a option to match milliseconds. I suggest to first remove them from your date, and only then parse the date with strptime:
use DateTime::Format::Strptime;
my $date = 'Apr 9 2017 3:45:00:505PM';
# Removing milliseconds from date
$date =~ s/:(\d{3})(?=AM|PM)//;
my $milliseconds = $1;
my $strp = DateTime::Format::Strptime->new(pattern => '%h %d %Y %I:%M:%S%p',);
my $start_date = $strp->parse_datetime($date);
# Taking into account the milliseconds that were removed earlier
$start_date->add(seconds => 1) if $milliseconds > 500;
say $start_date->strftime("%F %T");
I have to convert the GMT date to region specific date with format like "YYYY-MM-DD H:M:S".
Code developed is :-
use Time::Local;
($year,$mon,$day) = split /\-/, $ARGV[0];
($hrs,$min,$sec ) = split /:/, $ARGV[1];
$time = timegm( $sec, $min, $hrs, $day, $mon-1, $year-1900);
print scalar localtime($time), "\n";
But when I run it like :-
$ perl testDateGMTToLocal.pl 2018-10-29 11:49:33
It gives o/p converted in local time zone:-
Mon Oct 29 07:49:33 2018
But I want this o/p in below format
29-OCT-18 07:49:33
Thanks in advance.
I'd recommend to do it all using modules. The all-capable and very complete module is DateTime, and for this job you'd also need DateTime::Format::Strptime.
One other option is the simpler and much smaller core module Time::Piece
use warnings;
use strict;
use feature 'say';
use Time::Piece;
die "Usage $0 YYYY-MM-DD H:M:S" if #ARGV != 2;
my $time = join ' ', #ARGV;
my $tp = Time::Piece->strptime($time, "%Y-%m-%d %T");
my $local = localtime($tp->epoch);
say $local;
# In the desired format
say join('-', $local->mday, uc $local->month, $local->yy),
' ', $local->hms;
# If "Oct" is ok instead of block capitals for month abbreviation
say $local->strftime("%d-%b-%y %T");
This converts GMT time, with invocation as in the question, to the local time on my machine
Mon Oct 29 04:09:33 2018
29-OCT-18 04:09:33
29-Oct-18 04:09:33
where the middle one was asked for.
On some systems there is the %F format specifier for %Y-%m-$d.† There may be a defined format for 29-OCT-18, in which case you don't have to patch it by hand, but I am not aware of it.
† Or the module has its own formatting in which case that's portable. But origin of the error when it fails to do %F on my system isn't clear to me in that sense.
You can use
use POSIX qw( strftime );
print(strftime("%d-%b-%y %H:%M:%S", localtime($time)), "\n");
how do i get the current year in 4 digit this is what i have tried
#!/usr/local/bin/perl
#months = qw( Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec );
#days = qw(Sun Mon Tue Wed Thu Fri Sat Sun);
$year = $year+1900;
($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime();
print "DBR_ $year\\$months[$mon]\\Failures_input\\Failures$mday$months[$mon].csv \n";
This prints DBR_ 114\Apr\Failures_input\Failures27Apr.csv
How do I get 2014?
I am using version 5.8.8 build 820.
use Time::Piece;
my $t = Time::Piece->new();
print $t->year;
Move the line:
$year = $year+1900;
To after that call to localtime() and to become:
($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime();
$year = $year+1900;
The best way is to use the core library Time::Piece. It overrides localtime so that the result in scalar context is a Time::Piece object, you can use the many methods that the module supplies on it. (localtime in list context, as you have used it in your own code, continues to provide the same nine-element list.)
The strftime method allows you to format a date/time as you wish.
This very brief program produces the file path that I think you want (I doubt if there should be a space after DBR_?) Note that there is no need to double up backslashes inside a single-quoted string unless it is the last character of the string.
use strict
use warnings;
use Time::Piece;
my $path = localtime->strftime('DBR_%Y\%b\Failures_input\Failures%m%d.csv');
print $path;
output
DBR_2014\Apr\Failures_input\Failures27Apr.csv
One option to get the 4 digit year:
#!/usr/bin/perl
use POSIX qw(strftime);
$year = strftime "%Y", localtime;
printf("year %02d", $year);
You can also use
my ($y,$m,$d) = Date::Calc::Today();
$y variable will contain 2019
$m variable will contain 8
$d variable will contain 9
at the time of writing this answer ( 9th August 2019 )
The simplest way, I find, to get the year is:
my $this_year = (localtime)[5] + 1900;
I am reading in log data with the following time stamp format:
Sat Aug 07 04:42:21 2010
I want to convert it to something like this:
20100807044221
What is the best way to do this in perl? Thanks.
Use Time::Piece. (Core module since Perl 5.10.)
#!/usr/bin/perl
use strict;
use warnings;
use Time::Piece;
my $timestamp1 = 'Sat Aug 07 04:42:21 2010';
my $time = Time::Piece->strptime($timestamp1, '%a %b %d %H:%M:%S %Y');
my $timestamp2 = $time->strftime('%Y%m%d%H%M%S');
Date::Parse may not be installed on all your systems, so you may want to use the following snippet:
my ($sec, $min, $hour, $mday, $mon, $year) = localtime();
my $timestamp = sprintf( "%04d%02d%02d%02d%02d%02d",
$year+1900, $mon+1, $mday, $hour, $min, $sec);
print("Timestamp: $timestamp\n");
Timestamp: 20100819135418
This is what Date::Parse is for.
You specify language and corresponding date format, like (copied from the documentation):
$lang = Date::Language->new('German');
$lang->str2time("25 Jun 1996 21:09:55 +0100");
The above will return "epoch" value, AKA unix time value (what you need).
Edit: regarding your post, you only need the canonical date string like yyyy-mmm-ddd etc., therefore you can invoke POSIX::strftime for that. Furthermore, your date format is default, so you won't need the language call:
...
use Date::Parse;
use POSIX qw(strftime);
my $sec = str2time('Sat Aug 07 04:42:21 2010');
my $ymd = strftime "%Y%m%d%H%M%S", gmtime($sec);
print "$ymd\n";
...
Result:
20100807024221
Regards
rbo
perl -MPOSIX -le'print strftime "%Y%m%d%H%M%S", localtime'
never mind, you need to parse it first. that'll just print it out in your format.
I need to read the system clock (time and date) and display it in a human-readable format in Perl.
Currently, I'm using the following method (which I found here):
#!/usr/local/bin/perl
#months = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);
#weekDays = qw(Sun Mon Tue Wed Thu Fri Sat Sun);
($second, $minute, $hour, $dayOfMonth, $month, $yearOffset, $dayOfWeek, $dayOfYear, $daylightSavings) = localtime();
$year = 1900 + $yearOffset;
$theTime = "$hour:$minute:$second, $weekDays[$dayOfWeek] $months[$month] $dayOfMonth, $year";
print $theTime;
When you run the program, you should see a much more readable date and time like this:
9:14:42, Wed Dec 28, 2005
This seems like it's more for illustration than for actual production code. Is there a more canonical way?
Use localtime function:
In scalar context, localtime() returns
the ctime(3) value:
$now_string = localtime; # e.g., "Thu Oct 13 04:54:34 1994"
You can use localtime to get the time and the POSIX module's strftime to format it.
While it'd be nice to use Date::Format's and its strftime because it uses less overhead, the POSIX module is distributed with Perl, and is thus pretty much guaranteed to be on a given system.
use POSIX;
print POSIX::strftime( "%A, %B %d, %Y", localtime());
# Should print something like Wednesday, January 28, 2009
# ...if you're using an English locale, that is.
# Note that this and Date::Format's strftime are pretty much identical
As everyone else said "localtime" is how you tame date, in an easy and straight forward way.
But just to give you one more option. The DateTime module. This module has become a bit of a favorite of mine.
use DateTime;
my $dt = DateTime->now;
my $dow = $dt->day_name;
my $dom = $dt->mday;
my $month = $dt->month_abbr;
my $chr_era = $dt->year_with_christian_era;
print "Today is $dow, $month $dom $chr_era\n";
This would print "Today is Wednesday, Jan 28 2009AD". Just to show off a few of the many things it can do.
use DateTime;
print DateTime->now->ymd;
It prints out "2009-01-28"
Like someone else mentioned, you can use localtime, but I would parse it with Date::Format. It'll give you the timestamp formatted in pretty much any way you need it.
The simplest one-liner print statement to print localtime in clear, readable format is:
print scalar localtime (); #Output: Fri Nov 22 14:25:58 2019