Progress Bar

[jrm]

I would like to add a simple progress bar/indicator to a script. For example, print a %age progress of a for loop. My specific questions are:

- how do I print the figure in the same place on the screen for each iteration.

- is there a module for more fluffy dispays, e.g. a bar graph with automatic scale calibration etc.

Cheers
jrm

p.s. my boss says "this is business critical and if it is not done by the time he gets in in the moring I have to stay at my desk for another 70 hours".

[Ovid]

I am sure there are modules that can do the graph for you, but to print something in the same place on the screen, you should be able to use Curses.

For more information: perldoc -q "How do I do fancy stuff with the keyboard/screen/mouse?"

Cheers,
Ovid

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[talexb]

If you are looking for a really simple solution (like something that would run from a command line) then you can use a bar graph terminated with a "\r" ready for the next bar graph to overwrite it. So you'd get something like

[---+---|---+---|---+---|---+---]  0%
[XXX+---|---+---|---+---|---+---] 10%
[XXXXXXXXXXXX---|---+---|---+---] 37%
[XXXXXXXXXXXXXXXX---+---|---+---] 50%
[XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX-] 97%

I'm sure printf ( "%2d" .. ) and the x operator would come in handy to implement that. For something a little classier, Ovid's suggestion of curses will work great.

--t. alex

"Excellent. Release the hounds." -- Monty Burns.

[jrm]

Many thanks Ovid and talexb for 2 helpful replies.

After some thought I have gone for the Curses option, (a good excuse to learn Curses ?).

A quick attempt at the %age worked well, and once I spotted the endwin() function I was happy.

There does, however, seem to be a lack of perl-specific-Curses documentation...

Thanks again
jrm

[Anonymous Monk]

Here's an graphical example using Tk. I wrote this to measure the progress of a compile (count's .o's in the build directory), but it can easily be tweakified for your own purposes.
Enjoy.


use Tk;

sub tick;

$MYBUILDDIR="c:\\build"; #Dont forget to backslash the backslashes

$total_objects = 303; #Number of object files a full build would creat
+e
$progressbar_width = 2*$total_objects;
$progressbar_height = 50;
$timer_interval=10; #in seconds

$MW = MainWindow->new;
$MW->bind('<Control-c>' => \&exit);
$MW->bind('<Control-q>' => \&exit);

$canvas1 = $MW->Canvas(
  '-width' => $progressbar_width,
  -height => $progressbar_height,
  -background => 'black'
) -> pack;
$newval = 10;

$start = $MW->Button(
    -text         => 'Start', 
    -command      => sub {tick},
);

$start->pack(-side => 'left', -fill => 'both', -expand => 'yes');

sub tick {
    # Update the counter every 5 seconds
    $MW->after($timer_interval * 1000, \&tick);
    $num_objs = @objects = glob($MYBUILDIR . "*.o");
    print "\n$num_objs out of $total_objects built so far...";
    $newval = ($num_objs / $total_objects)*$progressbar_width;
    $canvas1->create ('rectangle','0','0',$newval,$progressbar_height,
+-fill=>'red');
} 

MainLoop;

[JojoLinkyBob]

Oops, I posted anonymously by mistaked. Oh well, no biggy.
=~Desertcoder

[TStanley]

A quick search for progressbars on http://search.cpan.org turned up several modules that you could use, such as Tk::ProgressBar and Term::ProgressBar.

TStanley
--------
"Suppose you were an idiot... And suppose you were a
member of Congress... But I repeat myself." -- Mark Twain

[count0]

If you fancy GUI's, gtk-perl has support for libgnomeui (Gnome::* Perl modules), which has a progress bar widget (Gnome::AppBar).

[unb0rn]

- how do I print the figure in the same place on the screen for each iteration

a _simple_ solution would be the escapes chars, like \r ou \b.
\r returns to the beggining of line; \b backs one caracter.
use inside print :-)