Time::Progress(3p)

NAME
Time::Progress - Elapsed and estimated finish time reporting.

SYNOPSIS
  use Time::Progress;

  my ($min, $max) = (0, 4);
  my $p = Time::Progress->new(min => $min, max => $max);

  for (my $c = $min; $c <= $max; $c++) {
    print STDERR $p->report("\r%20b  ETA: %E", $c);
    # do some work
  }
  print STDERR "\n";

DESCRIPTION
This module displays progress information for long-running processes. This can be percentage complete, time elapsed, estimated time remaining, an ASCII progress bar, or any combination of those.

It is useful for code where you perform a number of steps, or iterations of a loop, where the number of iterations is known before you start the loop.

The typical usage of this module is:

•   Create an instance of "Time::Progress", specifying min and max count values.

•   At the head of the loop, you call the "report()" method with a format specifier and the iteration count, and get back a string that should be displayed.

If you include a carriage return character (\r) in the format string, then the message will be over-written at each step. Putting \r at the start of the format string, as in the SYNOPSIS, results in the cursor sitting at the end of the message.

If you display to STDOUT, then remember to enable auto-flushing:

 use IO::Handle;
 STDOUT->autoflush(1);

The shortest time interval that can be measured is 1 second.

METHODS

  new
  my $p = Time::Progress->new(%options);

Returns new object of Time::Progress class and starts the timer. It also sets min and max values to 0 and 100, so the next report calls will default to percents range.

You can configure the instance with the following parameters:

min Sets the min attribute, as described in the "attr" section below.

max Sets the max attribute, as described in the "attr" section below.

smoothing
    If set to a true value, then the estimated time remaining is smoothed in a simplistic way: if the time remaining ever goes up, by less than 10% of the previous estimate, then we just stick with the previous estimate. This prevents flickering estimates. By default this feature is turned off.

smoothing_delta
    Sets smoothing delta parameter. Default value is 0.1 (i.e. 10%). See 'smoothing' parameter for more details.

  restart
Restarts the timer and clears the stop mark. Optionally restart() may act also as attr() for setting attributes:

  $p->restart( min => 1, max => 5 );

is the same as:

  $p->attr( min => 1, max => 5 );
  $p->restart();

If you need to count things, you can set just 'max' attribute since 'min' is already set to 0 when object is constructed by new():

  $p->restart( max => 42 );

  stop
Sets the stop mark. This is only useful if you do some work, then finish, then do some work that shouldn't be timed and finally report. Something like:

  $p->restart;
  # do some work here...
  $p->stop;
  # do some post-work here
  print $p->report;
  # `post-work' will not be timed

Stop is useless if you want to report time as soon as work is finished like:

  $p->restart;
  # do some work here...
  print $p->report;

  continue
Clears the stop mark. (mostly useless, perhaps you need to restart?)

  attr
Sets and returns internal values for attributes. Available attributes are:

min This is the min value of the items that will follow (used to calculate estimated finish time)

max This is the max value of all items in the even (also used to calculate estimated finish time)

format
    This is the default report format. It is used if report is called without parameters.

attr returns array of the set attributes:

  my ( $new_min, $new_max ) = $p->attr( min => 1, max => 5 );

If you want just to get values use undef:

  my $old_format = $p->attr( format => undef );

This way of handling attributes is a bit heavy but saves a lot of attribute handling functions. attr will complain if you pass odd number of parameters.

  report
This is the most complex method in this package :)

The expected arguments are:

  $p->report( format, [current_item] );

format is string that will be used for the result string. Recognized special sequences are:

%l  elapsed seconds

%L  elapsed time in minutes in format MM:SS

%e  remaining seconds

%E  remaining time in minutes in format MM:SS

%p  percentage done in format PPP.P%

%f  estimated finish time in format returned by localtime()

%b
%B  progress bar which looks like:

      ##############......................

    %b takes optional width:

      %40b -- 40-chars wide bar
      %9b  --  9-chars wide bar
      %b   -- 79-chars wide bar (default)

Parameters can be ommited and then default format set with attr will be used.

Sequences 'L', 'l', 'E' and 'e' can have width also:

  %10e
  %5l
  ...

Estimate time calculations can be used only if min and max values are set (see attr method) and current item is passed to report! if you want to use the default format but still have estimates use it like this:

  $p->format( undef, 45 );

If you don't give current item (step) or didn't set proper min/max value then all estimate sequences will have value `n/a'.

You can freely mix reports during the same event.

  elapsed($item)
Returns the time elapsed, in seconds. This help function, and those described below, take one argument: the current item number.

  estimate($item)
Returns an estimate of the time remaining, in seconds.

  elapsed_str($item)
Returns elapsed time as a formatted string:

  "elapsed time is MM:SS min.\n"

  estimate_str($item)
Returns estimated remaining time, as a formatted string:

  "remaining time is MM:SS min.\n"

FORMAT EXAMPLES
 # $c is current element (step) reached
 # for the examples: min = 0, max = 100, $c = 33.3

 print $p->report( "done %p elapsed: %L (%l sec), ETA %E (%e sec)\n", $c );
 # prints:
 # done  33.3% elapsed time   0:05 (5 sec), ETA   0:07 (7 sec)

 print $p->report( "%45b %p\r", $c );
 # prints:
 # ###############..............................  33.3%

 print $p->report( "done %p ETA %f\n", $c );
 # prints:
 # done  33.3% ETA Sun Oct 21 16:50:57 2001

SEE ALSO
The first thing you need to know about Smart::Comments is that it was written by Damian Conway, so you should expect to be a little bit freaked out by it. It looks for certain format comments in your code, and uses them to display progress messages. Includes support for progress meters.

Progress::Any separates the calculation of stats from the display of those stats, so you can have different back-ends which display progress is different ways. There are a number of separate back-ends on CPAN.

Term::ProgressBar displays a progress meter to a standard terminal.

Term::ProgressBar::Quiet uses "Term::ProgressBar" if your code is running in a terminal. If not running interactively, then no progress bar is shown.

Term::ProgressBar::Simple provides a simple interface where you get a $progress object that you can just increment in a long-running loop. It builds on "Term::ProgressBar::Quiet", so displays nothing when not running interactively.

Term::Activity displays a progress meter with timing information, and two different skins.

Text::ProgressBar is another customisable progress meter, which comes with a number of 'widgets' for display progress information in different ways.

ProgressBar::Stack handles the case where a long-running process has a number of sub-processes, and you want to record progress of those too.

String::ProgressBar provides a simple progress bar, which shows progress using a bar of ASCII characters, and the percentage complete.

Term::Spinner is simpler than most of the other modules listed here, as it just displays a 'spinner' to the terminal. This is useful if you just want to show that something is happening, but can't predict how many more operations will be required.

Term::Pulse shows a pulsed progress bar in your terminal, using a child process to pulse the progress bar until your job is complete.

Term::YAP a fork of "Term::Pulse".

Term::StatusBar is another progress bar module, but it hasn't seen a release in the last 12 years.

GITHUB REPOSITORY
<https://github.com/cade-vs/perl-time-progress>

AUTHOR
Vladi Belperchinov-Shabanski "Cade"

<cade@biscom.net> <cade@datamax.bg> <cade@cpan.org>

<http://cade.datamax.bg>

COPYRIGHT AND LICENSE
This software is copyright (c) 2001-2015 by Vladi Belperchinov-Shabanski <cade@cpan.org>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.