negative value support

[barcat.git] / graph

diff --git a/graph b/graph
index 2de4b90502073fa0122789a697fce3b6a298945d..01f68463e0c8779f8d974b8d0dfe679673da9444 100755 (executable)
--- a/graph
+++ b/graph
@@ -1,22 +1,40 @@
 #!/usr/bin/env perl
 use 5.014;
 use warnings;
-use List::Util qw( max );
+use List::Util qw( max sum );
+use open qw( :std :utf8 );
 
-my $width = $ENV{COLUMNS} || 80;
+our $VERSION = '1.00';
 
-my @lines = readline;
+use Getopt::Long '2.33';
+sub podexit { require Pod::Usage; Pod::Usage::pod2usage(-exitval => 0, @_) }
+GetOptions(\my %opt,
+       'color|c!',
+       'width|w=i',
+       'usage|h' => sub { podexit() },
+       'help'    => sub { podexit(-verbose => 2) },
+) or exit 64;  # EX_USAGE
+$opt{width} ||= $ENV{COLUMNS} || 80;
+$opt{color} //= 1;
+
+my @lines = readline or exit;
 chomp for @lines;
-my @values = map { s/^\h*([0-9]*)// and $1 } @lines;
+my @values = map { s/^\h*(-?[0-9]*)// and $1 } @lines;
 my @order  = sort { $b <=> $a } @values;
-my $lenval = 1 + int log($order[0]) / log 10;  # max string length
+my $maxval = max $order[0], -$order[-1];
+my $lenval = 1 + ($order[-1] < 0) + int log($maxval || 1) / log 10;  # max string length
 my $len    = 1 + max map { length } @lines;  # left padding
-my $size   = ($width - $lenval - $len) / $order[0];  # bar multiplication
-my $mean   = ($order[$#order / 2] + $order[$#order / 2 + .5]) / 2;
+my $size   = ($opt{width} - $lenval - $len) / $maxval;  # bar multiplication
+
+sub orderpos { ($order[$_[0]] + $order[$_[0] + .5]) / 2 * $size }
+my @barmark;
+$barmark[ sum(@values) / @values * $size ] = '=';  # average
+$barmark[ orderpos($#order / 2) ] = '+';  # mean
+defined and $opt{color} and $_ = "\e[36m$_\e[0m" for @barmark;
 
 for my $nr (0 .. $#lines) {
        my $val = $values[$nr];
-       my $color =
+       my $color = !$opt{color} ? 0 :
                $val == $order[0] ? 32 : # max
                $val == $order[-1] ? 31 : # min
                90;
@@ -24,7 +42,80 @@ for my $nr (0 .. $#lines) {
        printf "%*s", $lenval, $val;
        print "\e[0m" if $color;
        printf '%-*s', $len, $lines[$nr];
-       my $bar = '-' x ($val * $size);
-       substr $bar, int($mean * $size) - 1, 1, "\e[36m+\e[0m" if $val >= $mean;
-       say $bar;
+       print $barmark[$_] // '-' for 1 .. abs $val * $size;
+       say '';
 }
+
+__END__
+
+=head1 NAME
+
+graph - append bar chart to input numbers
+
+=head1 SYNOPSIS
+
+B<graph> [<options>] [<input>]
+
+=head1 DESCRIPTION
+
+Each line starting with a number is given a bar to visualise relative sizes.
+
+=head1 OPTIONS
+
+=over
+
+=item --no-color
+
+Disable colored output of values and bar markers.
+
+=item -w, --width=<columns>
+
+Override the maximum number of columns to use.
+Appended graphics will extend to fill up the entire screen.
+
+=back
+
+=head1 EXAMPLES
+
+Commonly used after counting, such as users on the current server:
+
+    users | sed 's/ /\n/g' | sort | uniq -c | graph
+
+Letter frequencies in text files:
+
+    cat /usr/share/games/fortunes/*.u8 |
+    perl -CO -nE 'say for grep length, split /\PL*/, uc' |
+    sort | uniq -c | graph
+
+Memory usage of user processes:
+
+    ps xo %mem,pid,cmd | graph -l40
+
+Sizes (in megabytes) of all root files and directories:
+
+    du -d0 -m * | graph
+
+Number of HTTP requests per day:
+
+    cat log/access.log | cut -d\  -f4 | cut -d: -f1 | uniq -c | graph
+
+Any kind of database query with leading counts:
+
+    echo 'SELECT count(*),schemaname FROM pg_tables GROUP BY 2' |
+    psql -t | graph
+
+Git statistics, such commit count by year:
+
+    git log --pretty=%ci | cut -b-4 | uniq -c | graph
+
+Or the most frequent authors:
+
+    git shortlog -sn | graph | head -3
+
+=head1 AUTHOR
+
+Mischa POSLAWSKY <perl@shiar.org>
+
+=head1 LICENSE
+
+GPL3+.