Plot spectrum vs time

I want to create a plot which show spectrum vs. time. Instead of a waterfall plot, I would like to have two axis:
- x: time
- y: frequency
The frequency axis will have 100 points. Each point represents the strength of the frequency in color (or I may use grayscale). For example:
- red: large amplitude
- orange: medium amplitude
- white: low amplitude
The graph will automatically scroll to the left as new data is added as a vertical column on colors. In this way, I can see how the frequency content changes over time.
Can this be done? I am using MS Visual Studio 6.0 C++. I have used ChartXY and PlotXY for plotting a single spectrum, and for other time based data.
Thanks!

Hi Bbuternowsky,
One way you could accomplish this would be to use a 3d graph control with the view set to be directly down the z axis. You can then assign a gradient to the z axis to obtain your z coloring. There are a number of examples showing the 3d graphing functionality of Measurement Studio:
C:\Documents and Settings\All Users\Documents\National Instruments\MStudioVS2008\VCNET\Examples\UI\3DGraph
The color map styles example in this folder demonstrates configuration of the z axis coloring, so that would be a good place to start!
Al B.
Staff Software Engineer - TestStand
CTA/CLD

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germ Remove "nospam" to reply

In article <[email protected]>,
chutla wrote:
> Greetings!
>
> You can use any of the 3D display vi's to show your "main" 3d
> data, and then use color to represent your fourth dimension. This can
> be accessed via the property node. You will have to set thresholds
> for each color you use, which is quite simple using the comparison
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> be just another vector (column) in your data file.
chutla, thanks for your post, but I don't want a 3D display of the
data....
> Also, check out
> the BUFFER examples for how to separate out "running" data in real
> time.
Not clear to me what you mean, but will c
heck the BUFFER examples.
> As far as autoscaling is concerned, you might have to disable
> it, or alternatively, you could force a couple of "dummy" points into
> your data which represent the absolute min/max you should encounter.
> Autoscaling should generally be regarded as a default mode, just to
> get things rolling, it should not be relied on too heavily for serious
> data acquisition. It's better to use well-conditioned data, or some
> other means, such as a logarithmic scale, to allow access to all your
> possible data points.
I love autoscaling, that's the way it should be.
germ Remove "nospam" to reply

How do I make an XY-Graph plot points over time?

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Message Edited by Dennis Knutson on 11-12-2007 06:32 PM
Attachments:
XY Graph 1.PNG ‏21 KB
XY Graph 2.PNG ‏6 KB

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Dear Preston Johnson,
Thanks for your prompt reply.
Now I am able to open the VIs, however i am getting some errors in executing them, which I am attaching with this post. I hope you get some clues from the error lists and help me in sorting them out.I am sorry for bothering you so much :-)
With regards
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Message was edited by: Jerrold Green1

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Message was edited by: stvelucky

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Plot spectrum vs time

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