Possibility to scale series

[Mickael-Martin]

hello,

I search a way to transform/scale one or more series to obtain graph like that :

I don't find any option to make that.

[goat1000]

I'm sorry, I don't understand what you are trying to do. The examples you gave look like line graphs with negative values.

[Mickael-Martin]

Hello,

No, it's positive values on Y negative axis. You can see legends in the second example, all values are positive. This feature is usefull to display bandwidth, for example :

[goat1000]

The easiest way to do that is to pre-process the values you pass to SVGGraph, and multiply all the values you want to be negative by -1.

// make series at array positions 3 and 4 negative
$negative_index = [3, 4];

foreach($values as $key => $row) {
  foreach($negative_index as $index) {
    $values[$key][$index] = $row[$index] * -1;
  }
}

[Mickael-Martin]

Yes, I know that, but you got wrong values. The idea is an additional Y axis inverted like grafana/grafana#38202 / grafana/grafana#44774

[goat1000]

OK, I'll add it to the list of things to look at.

[Mickael-Martin]

Thank you very much : I want to use that to extend Zabbix widget (svggraph widget use your project, do you know ?) to get beautiful graphs for bandwidth.

[goat1000]

Are you sure that Zabbix uses SVGGraph? I can't see anything about it.

[Mickael-Martin]

Oh no, I was very wrong. I have skimmed through the PHP classes and linked to your project. I'm really sorry for this blunder...
And the worst part is that two of us made the connection (with a colleague)... So you can close this "issue" if you like.
I am frankly ashamed.