How can I find the next x-axis point which will be used on a chart?

[davey31415]

Is there a value in property nodes which will tell me what the next x-axis point which will be used is on a chart?

Dave

[RavensFan]

Are you using a waveform chart?  Why do you want to know this?

All x values are evenly spaced.  So if you want to find the next x value you would look at the offset and multiplier properties of the X scale, and the array size of the history data.  So Offset + multiplier times size of history array will be the x value of the next point to be plotted.

[davey31415]

Waveform chart, yes. 

I ask because I am saving a simplified image of the chart each time the graph reaches a specific value (every 30 minutes, for instance).

I was keeping a separate count but would rather read from the chart itself. 

Using array size makes sense.

Thanks,

Dave