如何在RRD图参数的参数中添加公式

Question

E.g. I have following code,
our $timeseries = {
   _type      => 'array',
   _pdpstep   => 300,    # Time resolution
   _heartbeat => 700,    # Time of loss before going to Unknown
   _storage   => 'day',
   _ylabel    => "dBm",
   _mandatory => 'yes',
   # hwEntityOpticalRxPower dBm * 100
   ahwEORxPowre    => { label      => 'Rx Power',
                        type       => 'GAUGE',
                        probe      => '1.2.3.4.5.6.7.8',
                        min        => -3999,
                        multiplier => 0.01,
                      },
   # hwEntityOpticalTxPower dBm * 100
   bhwEOTxPower    => { label      => 'Tx Power',
                        type       => 'GAUGE',
                        probe      => '1.2.3.4.5.6.7.8',
                        # -4000 means no signal
                        min        => -3999,
                        multiplier => 0.01,
                      },
};

此数据在MW（毫米）中，我想将其转换为Descibel-Milliwatts（DBM），为此，我添加了具有0.01值的乘数。但是它不是在DBM中转换值。我怎样才能做到这一点？我可以在这里添加任何公式吗？

Answer 1

使用子例程并将数据传递给它。

data => calc(0.01),

然后在其他地方定义子例程

sub calc
{
    my $var = shift;
    return $var+100;
}