PERL RRDTTOL : graph subroutine with conditional legend

Question

愚蠢的事情我无法管理...

在 Perl 中，我使用 RRDTool(rrds 模块)创建了一个通用子例程来创建不同时间段(1 天、1 周...)的图表。我想使用一些子参数来显示可选图例。

使用以下代码，不会生成任何图形....

#!/usr/bin/perl
use strict;
use OWNet;
use RRDs;
use warnings;
use diagnostics;

my $rrd = '/var/rrd/electricite.rrd';
my $img = '/mnt/ds211/web/';

&CreateGraph("conso","Consommation electrique 1 heure","1h",1);

sub CreateGraph
# inputs:   $_[0]: sensor_rrd_name
#       $_[1]: chart title
#       $_[2]: interval period (1h,24h,7d,1m,1y,10y)
#       $_[3]: Puissance instantanee (1/0)
{
    my $temp_graph;
    $temp_graph ="\"$img$_[0]-$_[2].png\",";
    $temp_graph .="\"--start=end-$_[2]\",";
    $temp_graph .="\"--end=now\",";
    $temp_graph .="\"--width=600\",";
    $temp_graph .="\"--height=200\",";
    $temp_graph .="\"--slope-mode\",";
    $temp_graph .="\"--title=$_[1]\",";
    $temp_graph .="\"--vertical-label=Watt\",";
    $temp_graph .="\"--lower-limit=0\",";
    $temp_graph .="\"--alt-autoscale-max\",";
    $temp_graph .="\"DEF:energy=$rrd:$_[0]:AVERAGE\",";
    $temp_graph .="\"CDEF:Watt=energy,3600,*\",";
    $temp_graph .="\"LINE2:Watt#0000FF:\",";
    $temp_graph .="\"AREA:Watt#00FF00:\",";
    $temp_graph .="\"VDEF:WattHour=energy,TOTAL\",";

    if ($_[3]==1)
    {
        $temp_graph .="\"GPRINT:Watt:LAST:  Puissance instantanee\\: %6.2lf%sW\",";
    }

    $temp_graph .="\"GPRINT:WattHour:   Consommation totale\\: %6.2lf%sWh\\n\",";
    $temp_graph .="\"GPRINT:Watt:MIN:  Puissance min\\: %6.2lf%sW\",";
    $temp_graph .="\"GPRINT:Watt:AVERAGE:  Puissance moyenne\\: %6.2lf%sW\",";
    $temp_graph .="\"GPRINT:Watt:MAX:  Puissance max\\: %6.2lf%sW\"";

    RRDs::graph ("$temp_graph");

    if ($ERROR = RRDs::error)
    {
        print "$0: failed to generate graph $_[0] data into rrd: $ERROR\n";
    }
}

谢谢

Answer 1

问题是您向 rrdtool 传递一个字符串而不是带有参数的数组。

代替

RRDs::graph ("\"graph.gif\",\"DEF:...\" ...");

你应该打电话

RRDs::graph ("graph.gif","DEF:...","...");`

如果你想事先准备好你的论点，那么你可以使用

my @args = ("graph.gif","DEF:...","...")
RRDs::graph(@args);

希望这对您有所帮助。