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How to set name and Range of X-axis in waveform-display

Hello,
i have recorded a trace which should be displayed in a graph.
The graph displays the x-axis with default-name = "time" and starts at "0" and ends at the number of points of my trace.
My question is:
1. How can i change with property the name "time" to another name?
2. How can i change with property the start-number to another number (= start-frequency)?
3. How can i change with property the last number (= stop-frequency)?

I recorded a trace with 1000 points in a special frequency-range. The first point of the trace should now have as x-value the corresponding frequency.
Thx for your help.
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Message 1 of 12
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If you are using a waveform graph, you can use the following properties
 
 
If you are using an XY chart, you can use exactly the same thing, but link the property node to the XY graph instead. You can also change the increment.


Message Edited by jrpe on 11-14-2007 09:25 AM
Jeff


Using Labview 7 Express
Message 2 of 12
(4,587 Views)
Hi jrpe,
it works but not as i want.
When i change XScale.Minimum & Maximum then the whole graph i moving to this position.
My trace values start at 0 and end at 200, but when i change the xScale then this position is no more visible.
I attached an example of what i mean.

I have as input:
1.) the trace
2.) start-frequency
3.) Stop-freuquency

And i want to display the first trace-point in the graph at x-position = start frequency
and the last trace-point at x-position = stop-frequency.

How can this be done?
Thx

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Message 3 of 12
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I couldnt see your vi because I only have 7.0.
 
If I understand your problem, you have a trace from start frequency to end frequency. You can use those properties to set the scale range, however regardless of your start frequency, your trace is being plotted from 0, so say you have a trace from 50Hz to 200Hz the scale is right...but the actual data is being plotted from 0 to 150?
 
If so, there is a property in Xscale --> Offset and Multiplier --> Offset. The offset property will let you adjust your starting point.
 


Message Edited by jrpe on 11-14-2007 11:48 AM
Jeff


Using Labview 7 Express
Message 4 of 12
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I did you you said and attached a screenshot.
Can you explain why the trace looks different in the two graphs?
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Message 5 of 12
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The problem is:
When i have a trace with 1000 points with start = 500Hz and stop = 600HZ, then the displayed graph has only 100 points, and  that means only trace-points 0..99 are displayed, the rest is invisble.

I think i have to create a XY-trace where Y is my trace and X is a computed trace "from start to stop".
Can this be done?
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Message 6 of 12
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Your trace has 200 data points.  On the first graph, you have not adjusted the properties so it displays from 0-200
On the second graph, you set the min to 500 and the maximum to 600, which is a range of only 100. So only half of your trace is being displayed. Since it appears to me that you are taking 200 samples over 100Hz, your increment needs to be adjusted. By default, the increment is 1 on the waveform, so that corresponds to 1Hz. Since you have a data point every 0.5Hz, you need to change the property XScale.Increment to be equal to the difference between your start and end frequency divided by number of points in your trace (200). In this case, that is 100/200 = 0.5. See the following




Message Edited by jrpe on 11-14-2007 12:42 PM
Jeff


Using Labview 7 Express
Message 7 of 12
(4,544 Views)
wait I just read your new post.
 
You have 1000 data points. They represent frequency between 500Hz and 600Hz. I dont understand what you mean by the display has only 100 points. It will display all of the points, you just cant see them all because they are so close together, the 100 that you are seeing is the Frequency represented by those points. If you have 1000 points, each one is 0.1Hz incremented, so you will see points over a range of 100 (Hz). If you want to see more of the points distinctly, make your graph bigger.
 
If you implement what I just posted, it should work like you originally wanted.
Jeff


Using Labview 7 Express
Message 8 of 12
(4,537 Views)
Ok, now i created a ramp and use a XY-graph. Works (i hope)
Thx for your help
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Message 9 of 12
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Try this instead. No property nodes, no ramp function, no XY Graph.



Message Edited by Dennis Knutson on 11-14-2007 11:21 AM
Message 10 of 12
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