Labview XY Graph - multiple Y

[nkritsch]

I will use the XY-Graph to Display one X and 3 Y Axes. Like this: http://www.eng.auburn.edu/~niuguof/2210labdev/html/_images/bjt-iv.png

how can i do it?

I tried the Waveform Chart but in dont have an X Axes.

And i have an for loop where i generate data.

Can i Plot the Data while the for Loop is running?

If i use XY Graph i must wait before the Loop is over and then the Data will be plotted.

[GerdW]

Hi nkritsch,

do you really need 3 Y axes? Or do you want to have 3 plots in your graph? Your example picture only shows a graph with one Y axis and showing 5 plots…

- Use a graph rather than a chart. Graphs offer much more possibilities!

- Each chart/graph has a X axis, so please describe your problem more detailed!

- You can plot data while the loop is running. THINK DATAFLOW: the indicator has to be in the loop then…

- The same applies to a XY graph: it also can show data while the loop is running. THINK DATAFLOW…

[nkritsch]

thanks,

i need to have 3 plots in my graph with the same X Axe. Like in the example.

i tried using an XY-Graph (Labview 2012)

thanks for the Dataflow....dont thought about it

[altenbach]

You seem to be confused.

• In the title you talk about xy-graphs, so why are you trying to use a chart?
• Your graph only has one Y-axis, shared by all plots.
• Your graph has all plots sharing the same x-axis and the points are spaced equally, meaning a plain graph (not chart or xy) is sufficient.
• If you want to interactively fill the graph (plain or xy) as data is generated in a loop,  you need to build the data in a shift register. Do you have problems with that?

To graph multiple plots on a plain waveform graph, you need a 2D array with one row per plot. You also need to adjust x0 and dx for the x-axis corresponding to the actual x-axis scaling.

[Dennis_Knutson]

What example? You can use either a chart, graph, or xy graph. If you've taken any LabVIEW class or free tutorial, you should understand the differences. A chart is typically used for when you a acquire a single point for 1 or more channels at a regular interval. A graph is used when you acquire multiple points for 1 or more channels at a regular interval. An xy graph is used when you sample at irregular intervals. The image you posted could have used any one of the three.

[nkritsch]

yes i have irregular Intervals so i need the XY Graph (which i use)

But i will doing the "same" like in the picture.

I Start on a Voltage...get the 3/5 Current Values then i go to the next voltage step and so on.

It can be only build by an XY Graph.

So i want get multi Plots in 1 Graph.

[GerdW]

Hi nkritsch,

the context help for the XY graph shows how to create multiple plots!

[Dennis_Knutson]

The picture has regular intervals on the x axis so you are obviously doing something different. You need to attach your VI or an image of the block diagram since your description is inadequate.

[nkritsch]

ah ok when i found an example thanks.

i will build somethink little different so the Voltage wont be the Same

[GerdW]

Hi Dennis,

in the picture attached to the first post the voltage is measured with atleast 5 digits (as displayed below graph). So the voltages between the points of those plots may differ in the µV-range. A XY graph would be fine then…