Chart::Graph::Gnuplot Array Issue

vbrtrmn has asked for the wisdom of the Perl Monks concerning the following question:

Monks, I'm a bit rusty with Perl, I took a hiatus to learn TCL. I'm having an issue with Chart::Graph::Gnuplot, today. Using the General Example from CPAN, I always seem to return an error message, I'm fairly certain that I'm passing the data set as an array, though I may be smoking the crack.. Error:

Data set must be an array at gnuplot.cgi line 9
[download]

General Example

  use Chart::Graph::Gnuplot qw(gnuplot);
  gnuplot({"title" => "foo",
           "x2-axis label" => "bar",
           "logscale x2" => "1",
           "logscale y" => "1",
           "output type" => "png",
           "output file" => "gnuplot1.png",
           "xtics" => [ ["small\\nfoo", 10], ["medium\\nfoo", 20], ["l
+arge\\nfoo", 30] ],
           "ytics" => [10,20,30,40,50]},
           "xdata" => "time",
           "format" => ["x", "%m/%d"],
           "timefmt"=> $date_format,
           "extra_opts" => "set key left top Left",
          [{"title" => "data1",
            "type" => "matrix"}, [[1, 10],
                                  [2, 20],
                                  [3, 30]] ],
          [{"title" => "data2",
            "style" => "lines",
            "type" => "columns"}, [8, 26, 50, 60, 70],
                                  [5, 28, 50, 60, 70] ],
          [{"title" => "data3",
            "style" => "lines",
            "type" => "file"}, "samplefile"],);
[download]

Any help is apreciated!

--
paul

Comment on Chart::Graph::Gnuplot Array Issue Select or Download Code

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Re: Chart::Graph::Gnuplot Array Issue by naChoZ (Curate) on Jul 21, 2004 at 23:11 UTC
You can do it without necessarily bothering with that module. Abigail-II told me how he does it, so here's a snippet I wrote. # {{{ ->create graph method # sub create_graph { my $class = shift; open my $plot => "\| /usr/local/bin/gnuplot" or die "Failed to open pipe: $!\n"; my $outfile = "/tmp/graph.png"; print $plot <<" --"; set terminal png color set out "$outfile" set format x "/%b%y/" set xdata time set key left top Left reverse samplen 2 title "Legend" box set timefmt "%s:" set grid xtics ytics set xtics nomirror set ytics nomirror set y3tics nomirror set autoscale set ylabel "ResponseTime" plot "$_[0]" using 1:2 smooth unique axis x1y1 title "Time in +ms" -- #set timefmt "%Y-%m-%d:" close $plot or die "Failed to close pipe: $!\n"; chmod 0644 => $outfile or die "Failed to chmod $outfile: $!\n" +; } # }}} [download] I just pass it a filename (which I had previously created with File::Temp). `My::Class->create_graph( $filename );` -- "A long habit of not thinking a thing wrong, gives it a superficial appearance of being right." -- Thomas Paine naChoZ	[reply] [d/l] [select]
Re^2: Chart::Graph::Gnuplot Array Issue by vbrtrmn (Pilgrim) on Jul 21, 2004 at 23:41 UTC
DUDE, YOU ROCK! Thanks a lot! -- paul	[reply]
Re: Chart::Graph::Gnuplot Array Issue by vbrtrmn (Pilgrim) on Jul 22, 2004 at 18:24 UTC
If anyone is starting out with gnuplot, here are some good resources (thanks to naChoZ I got my script working in a couple hours!): I would recommend the mailing list, though the answer I got back with no help just a simple RTFM. Gnuplot SourceForge Page Gnuplot Demo Scripts Gnuplot Wiki Page with Sandbox Not So FAQ (excellent!) -- paul	[reply]
Re: Chart::Graph::Gnuplot Array Issue by kryberg (Pilgrim) on Jul 22, 2004 at 18:31 UTC
I've done it another way from the one already suggested. I use LWP::UserAgent to get data from a URL, save it to a file because it is a very large dataset I use more than once, do a bunch of manipulations, ultimately putting the data into arrays (`@dates` and `@atemp` in the code below) for various graphs, then graph. gnuplot({ "title" => "", "output type" => "png", "output file" => "temp.png", "x-axis label" => "$day.$month.$year $time - $eday.$emonth.$ey +ear $etime", "y-axis label" => "", "xdata" => "time", "format" => ["x", "%d.%m"], "timefmt" => "%Y-%m-%d-%H:%M", "xrange" => "[\"$dates[$index]\" : \"$dates[$j]\"]", "extra_opts" => join("\n","set grid", "set nokey", "set linest +yle 1 lt 3 l w 10","set lmargin 10","set rmargin 10","set tmargin 9","set bmargin 9 +" )}, [{ "style" => "lines ls 1", "type" => "columns"}, [@dates],[@atemp] ],); my $type = "AirTemp.png"; my $ftype = "Days" . "$days" . "ATemp.png"; my $finalgraph = printGraph($station,$type,$ftype); } [download] In case anyone notices/wonders/tries to use this, some things are intentionally left blank and the file is called temp because I ultimately use GD to splice this onto a background image using the subroutine at the end called printGraph - I just thought I'd include the whole code block because I know it works.	[reply] [d/l] [select]


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