xy graph multi plots

[mdstitt]

Hello,

I have a need to plot a curve on an X-Y graph which is Voltage (Vsd) vs Current (Isd). After the first plot, I need to set another voltage (Vg) to a new level and repeat the plot. I would like to do this without erasing the original plot so I can generate a family of curves. Currently, I am using one trace on the graph which traces to zero at the beginning of the next plot. I need to create an entirely new plot on the graph instead of the original going to zero at the beginning of each plot. I cannot plot all curves at the same time because the voltage (Vg) level will change with each curve. Any suggestions will be appreciated.

Thanks,

Mark

[Anthony_de_Vries]

Maybe I misunderstand the question...

Multiple plots on the XY-graph, means you need to put them in an array.  If you don't have all the graphs at once, then you could simply build the array dynamically.   I.e. you put the array in a shift register, and add elements (measurements) to it as you go.

See the attached vi for an example.

[pawel]

put all XY plots into the array.

You can create another scale as well by right clicking on the scale and selecting duplicate.

take care

Pawel

[mdstitt]

I'm sorry, but I am still unable to acheive two plots on the same xy graph. I also was unable to open the attachment because it was Labview 8 and I have 7.1. I do not know how to increment the array to advance to the next plot. Also, for the xy graph, I have to use an array of clusters. My program is essentially a state machine, where the first state sets up the constant voltage and the next state ramps the variable voltage and records the current and voltage. How can I tell it that the next element is plot 2, then plot 3....? By building the array dynamically, it always wants to display the data as plot 1. I just end up with a mess on the graph. Thanks for trying to help.

[pawel]

OK,

did you try to look up examples. There is more than plenty for XY graphs.

take care

Pawel

[Dennis_Knutson]

Here's a simple example. Since you haven't posted your code, I can only guess what you're doing wrong. With each iteration, you should be creating

a cluster with an x and y array and then use the build array to create a 1D cluster array.

[johnsold]

Mark,

Perhaps this attachment will help you sort out the use of graphs. It is something which I put together to test plotting a family of curves for my current project. It generates ellipses rather than using externally acquired data. Each ellipse is offset vertically from the previous one for visibility.

Lynn

[AndrewAlford]

Here's a way using a state machine to produce 4 plots.

[Atyab]

Hi Everyone,

      Lets consider the situation when we have no for loops and stuff. Just getting two coordinates at a time. Now, how do I plot two graphs at the same time?

[johnsold]

If you have no loops, how do you get enough points to plot?

Lynn