How to place a Reference Plot inside Acquired Data Graph?

[Mike415]

Hi,

I'm trying to set up the driver for an HP 4396a to display a set reference plot alongside an acquired data plot (From HP 4396a) inside of the same graph.  So one plot that is always there and one plot that shows data retrieved from the Network Analyzer.  I have tried using the "Read from Measurement File", but with no luck.  Hopefully in the end I can have those two plots, along with the cursor legend on the acquired data plot and two constant Y value lines for reference.

Thanks
Mike

[MikeS81]

Hi Mike,
i don´t know the device, but i think you can receive the data from it and plot it with the other data into one graph. How do you do it at the moment?

Mike

[Dennis_Knutson]

As the on-line help and shipping examples show, there are a couple of ways to create a multi-plot graph. A 2D DBL array, a 1D waveform data type array, a cluster array, etc. You can certainly use the Read From Measurement File but you would need to convert the dynamic data output to match the data type you are currently plotting. Provide that information and someone can help. simply saying you have had no luck is not much to go on.

[Mike415]

Right now it is already set up to plot the data onto a Graph, but Im trying to get that same graph to display constant Y Values across and a Plot that was already created.  The image is where I am at right now.  It is the Acquired Data in Green and the formula plot in red which is plotted on an invisible graph and superimposed on.  This will work for me if I can get that red graph to display the correct information such as a previously chosen plot.

Thanks
Mike

[Dennis_Knutson]

An image of the front panel is not what I was talking about. That tells nothing about the data type that you are plotting and the data type of the file. If you don't want to post the actual VI, at least post an image of the block diagram.

p.s. Constant Y values across? Do you really mean constant X values?

[Mike415]

Sorry Dennis I was trying to reply to Mike.  But I'll try to explain what Im trying to do better.  I'm new to LabVIEW and programming in any language so this is extremely hard for me to understand.  But I have driver for a 4396a to acquire data from the Network Analyzer and plot it on a graph. 

The next step I'm trying to get to is a plot on that same graph for somebody to look at and see if the plot acquired from the 4396a matches closely enough to pass.  The attached .llb is where I am at with the superimposed plot, but I need for that superimposed plot to be a previously retrieved plot.  The bottom graph is my attempt at the .lvm Read from Meas.

Sorry and Thanks
Mike


EDIT: Now that I see it, with the graph superimposed on top the cursors are no longer accessible which is a slight problem.  So the better way is to get it to display on the graph, but still get the cursors to follow the acquired data and have the "Store Data" only save the acquired

Message Edited by Mike415 on 07-21-2008 12:58 PM

[Dennis_Knutson]

There is no Read From Measurement File in the top level VI that you posted. I'm having a hard time telling what is going on in the program. You could simply it considerably by using an event structure on the block diagram and I think a tab cotnrol on the front would make some sense as well. You really need to cut down on the local variables as well.

In any case, what you are using is actually an XY graph. The X array and Y array are bundled together. In order to add another plot, I think you will need to keep this in a shift register and in the case/event where you read from file, build a new x array and y array from the file and add this plot by using a Build Array function on the shift register data.

It also looks like you have a completely custom file format. Since this VI does not use the Write to Measurement File, you will need a custom file read in order to get the correct data.

[Mike415]

Heres a .lvm (Change .txt to .lvm) Im trying to use as a a test plot and a new .llb

The .llb I posted was a downloaded driver that I just changed a very small amount


Message Edited by Mike415 on 07-21-2008 01:21 PM

[Dennis_Knutson]

What is that data supposed to represent? If I use an XY Graph like you have in your program, I see the plot below.

Message Edited by Dennis Knutson on 07-21-2008 02:36 PM

[Mike415]

Its going to be a plot that represents the Impedance or Phase relative to different frequencies.  The data for it will be recieved from the Network Analyzer and maybe cleaned up to be the reference plot for future acquisitions.  So Impedance or phase relative to different frequencies.  I was unable to see the graph that you just posted after trying to display it on the new transparent graph.

Thanks