my %count=();  # A hash -it is bcos of of key/value pairs?

Yes, this declared a hash to store the results of counting the lines. The key will be one of either 'CLEAN','SPAM','INFECTED','BANNED','BAD_HEADER','REJECTED' and the value is the count.

while (<$fh>){

Read each line of the file into $_

  if (/amavis.*(Passed|Blocked) (CLEAN|SPAM|INFECTED|BANNED)/){

Match the line read (in $_) against the regex pattern like grep. The first word captured (Passed or Block) will be in $1 and the second (CLEAN or SPAM or INFECTED or BANNED) will be in $2 

    ++$count{$2}; # Why ++$count? why {$2} here? is it bcos of (Passed
+|Blocked) ?

[download]

For example, if $2 is the word CLEAN increment the hash $count{'CLEAN'}

  } elsif (/amavis.*(BAD-HEADER)-/) {
    ++$count{$1}; # why {$1} here? is it bcos of (BAD-HEADER)

[download]

Yes, this regex has only 1 set of brackets so if it matches the word BAD-HEADER will be in $1

  } elsif (/reject/){
    ++$count{'REJECTED'}; #Hmm, Why {'REJECTED'}?
  }
}

[download]

I chose REJECTED because 'rejected' was the label in your graph and all the other keys are upper case

my @data = map{ $count{$_} || 0 } qw(CLEAN SPAM INFECTED BANNED BAD-HEADER REJECTED);

map is a convenient way of creating an array from another another array. It is the same as

my @data=();
$data[0] = $count{'CLEAN'} || 0; # use 0 if $count{'CLEAN'} is undefin
+ed 
$data[1] = $count{'SPAM'} || 0;
$data[2] = $count{'INFECTED'} || 0;
$data[3] = $count{'BANNED'} || 0;
$data[4] = $count{'BAD-HEADER'} || 0;
$data[5] = $count{'REJECTED'} || 0;

[download]
poj

In reply to Re^7: problem with show_values => 1, while drawing a bar graph with variables by poj
in thread problem with show_values => 1, while drawing a bar graph with variables by theravadamonk

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