How to plot whole history data on a XY-graph if the data size is too big.

[parthabe]

appforce wrote:

Is there any way to get a chunk of data and plot these data first and then get another chunk of data, plot the data, and still hold the previous data on the plot?

If you want to hold the history data for a plot, you have to use the Waveform Chart instead of the Waveform Graph, because the former has the property called History Data while the latter does not.

Hope it helps...

[altenbach]

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appforce wrote:
 Here is the VI.

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You have to be kidding! You have a huge file and...

1. read it line by line in a while loop
2. monitoring file positions
3. with each iteration converting two data points to a 2D array (!!)
4. followed by indexing out the two values with two seperate index nodes
5. form an xy cluster
6. built a cluster array at the loop boundary
7. bundle the array
8. make the cluster into an array with one huge element
9. feed it to a 2D graph.
10. Surround everything with a useless sequence frame!

Point 7 and 8 are completely useless, you can wire the output from the indexing node direclty to the graph terminal. Try it!

There is a primitive to read such files in one step.

The following code does exactly the same

Message Edited by altenbach on 05-07-2008 12:11 PM

[appforce]

Hello,
 Thank you very much. It makes my program running much faster than it did.


Best Regards,

Benjamin Chu