05-04-2012 09:53 AM
I wish to plot a single set of data on a chart and show it with multiple Y axis scales. This will be used for example to show raw data as voltage as well as its corresponding scaled converted value to watts. This can be done by first scaling the raw data and then sending those two (raw voltage and scaled watts) values to the chart. I'd like to avoid the memory and even the coding for multiple plots by only plotting the original data and somehow configuring a scale factor for a second Y axis. The second Y axis can be added using Duplicate Scale. One approach is to use the property nodes Y Scale > Range > Maximum and Minimum of the raw data and scaling those by the scale factor and writing that to the second Y Scale range Max and Min. This requires doing that every time new data is added to the chart. I was hoping instead the Y Scale Multiplier property node could do this but it doesn't seem to work properly after data is changed.
05-04-2012 09:57 AM
Have you looked at stack plots (same window with multiple charts with the same time base)? Are you looking to plot it in the same data window (single plot with multiple axis)?
05-04-2012 10:11 AM
I prefer overlay plots. Same data window, single plot area with multiple Y axis but only one single data set fed to the chart. The additional Y axis are simply derived from that single data set's Y axis by applying a scaling factor. The additional Y axis are there just for display as they do not actually have data associated or assigned with them thereby saving memory and coding to generate such scaled data. i.e. do not generate a scaled copy of the data but instead show just additional axis with a different scaled range.