in reply to Re: Re: Re: BASIC MATH WITH DATA
in thread BASIC MATH WITH DATA

OK....This is almost there..... thanks for the <IN> tip.... it looked like a small correction... it's gotta be in there... thanks 

#!/usr/bin/perl -w
       $infile = shift;
       $outfile = shift;
       
       open(IN, $infile) || die("Can't open input file $infile - $!");
       open(OUT, ">$outfile") || die("Can't open output file $outfile 
+- $!");

       use strict;
       my $text;
       my @lines;
       

#my @tmp = split /:/, $lines[-1];   these two go together
#my $last = $tmp[3];                 as an alternate way of doing this
+ routine
#                                    learn this in next attempt
     
       while (<IN>) {
         push @lines;
         shift @lines if @lines > 10;
       }

       chomp(@lines);

       my @cols;
       my $total = 0;

       for (@lines) {
         @cols = split /:/;
         $total += $cols[3];
       }
       my $average = $total / (@lines || 1);
         # if no lines, avoid division by zero

       my $last = (split /:/, $lines[-1])[3];

 $text = "Average of column 3 for the last " .
                              scalar(@lines) . " days: $average\n";   
+    
  $last ="Last value in Col3" . scalar(@lines) . " value: $last\n";

      print OUT "$text\n";
      print OUT "$last\n";

    
       close IN;
       close OUT ;
  
   
<\code>
 The message in the log file reads.....

<code>

Average of column 3 for the last 0 days: 0

Last value in Col30 value:

[download]
Lights are flashing on my machine.... files are poping on the screen.... this is good.... but what am I missing .... all the values read "0" I have run this script through the Perl Builder debugger and it does not indicate errors...which is too bad. There are obviously still some errors in here. Would someone please have a look.... Thanks Joachim

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(tye)Re3: BASIC MATH WITH DATA
by tye (Sage) on Jan 26, 2001 at 07:09 UTC

    If you are comfortable using the debugger, now would be a good time to fire it up: "perl -d script.pl". If you aren't comfortable, then you might consider this as a good time to get comfortable. (: Otherwise, I suggest you get more data. Data::Dumper is great for this, but you could start with just a: 

    print "($cols[3]) $_";

    [download]
    just above the $total += $cols[3]; line.

            - tye (but my friends call me "Tye")
[reply]
[d/l]
[select]
      tye...... thank you for having a look. I can see that you trying to get the data to dump.... I tried your line entry and ..... nothing dumped .... in short the code is running but not doing the calculation. As for data...... I am trying to do the calculation for a 10 entry average.... the test file is 31Kb of data.... more than sufficient for this small program. We should be able to get a 200 event average with that amount of data. 
      #!/usr/bin/perl -w
       use strict;
       
       
       $my infile = shift;
       $my outfile = shift;
       
       open(IN, $infile) || die("Can't open input file $infile - $!");
       open(OUT, ">$outfile") || die("Can't open output file $outfile 
+- $!");

              my $text;
       my $text2;
       my @lines;
      
       while (<IN>) {
         push @lines;
         shift @lines if @lines > 10;
       }

       chomp(@lines);

       my @cols;
       my $total = 0;

       for (@lines) {
         @cols = split /:/;
        print "($cols[3]) $_";
         $total += $cols[3];
       }
       my $average = $total / (@lines || 1);
       

                # if no lines, avoid division by zero
         
          my $last = (split /:/, $lines[-1])[3];

       
 $text = "Average of column 3 for the last " .
                              scalar(@lines) . " days: $average\n";   
+    
  $text2 ="Last value in Col3 " . 
                              scalar(@lines) . "  $last\n";

      print OUT "$text\n";
      print OUT "$text2\n";

    
       close IN;
       close OUT ;

      [download]
      **** this is the best edited version till now.... have a look..... it would be easy to give up in frustration.... it's being able to do caculations like this .... is what scripting is all about... for me anyway. Especially when you can see ways of doing the work faster and simpler than in Excel .... once you get it coded right that is.. Joachim
[reply]
[d/l]

        If not output, @lines is empty. Add ", $_" on the end of your push statement: 

        push @lines, @_;

        [download]

        This bug was mentioned elsewhere, I recall. ;)

                - tye (but my friends call me "Tye")
[reply]
[d/l]

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