multiple axes

[gasma1975]

Hi,

I'm using Labwindows/CVI 6.0, is it possible to have 6 independant Y axes on the same graph, I really need to plot 6 Waveforms with different scales on the same graph. Anyone have an idea ?

Thank you,

gasma1975

[Chris Matthews]

Unfortunately, our CVI native graphs only support up to 2 Y axes. We do supply an ActiveX Graph control with Measurement Studio that has support for that many Y axes. That would require you to program it with ActiveX programming though which you may not have experience with in CVI. I included an example that shows you how this is done (ActiveX control graph with 6 axis).

If you haven't done ActiveX programming in CVI before, this example may be confusing. I setup the 6 axes and the 6 plots in the property pages of the ActiveX control graph. Then wrote a few lines of ActiveX programming in the plot function to send some sine waves to the graph plots.

Best Regards,

Chris Matthews
National Instruments

[gasma1975]

Thank you,

I would like to know is your Example only valid in the Labwindows CVI 6.0 ?, I've tried it on V5.5.1 and It doesn't work...

Thank you,

[Chris Matthews]

Yes, it's only valid in CVI 6.0. ActiveX control support was new in version 6.0. You had stated that you were using CVI 6.0.

Chris

[RobertoBozzolo]

One solution I found to obtain it is to use one graph to display two axes and all plots, and to add some more graphs to display additional scales as needed.
In the example attached, I use a graph to display plots and two axes (power and torque), and two more graphs for the additional scales (tension, speed and efficiency). Some attention must be payed to the correct arrangement of datas and scales, since some plots are drawn in a graph but its corresponding scale is on another. In the source file you'll find my solution to it.
I hope I have helped you.
Roberto