Plot VDT data vs. Real Time

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My data is obtained from the RS-232 port (Data is accumulated in a For Loop by using VDTWrite2 command). I am having problem with graphing the data vs. real time. I saw an old post suggested to read The Slow Data Acq code, but it is too overwhelming for my level of coding. Can you be specific on how to display this data vs. time ?
Not really sure what you are asking. Are you asking about making your horizontal axis show date/time? or perhaps how to code the times when your data points are acquired?

John Weeks
WaveMetrics, Inc.
support@wavemetrics.com

November 13, 2015 at 03:44 pm - Permalink

I use VDTRead2 command to read my data from the Rs-232 ports (in a For Loop), but I basically don't know how to graph from there.

I can print out my data from the command below: (This gives me real time and data points as the For Loop runs)
Printf "%s %.2f %.2f \r" Secs2Time(DateTime,3,2),GasA, GasB

But I dont know how to plot GasA vs. time. ( Yes, time is the horizontal axis)
I try the display command, it appears as an empty graph.
Could you please walk me through this?
Thank you,

November 15, 2015 at 01:31 pm - Permalink

I presume that GasA and GasB are variables, and that the stumbling block is that you need to put your data into Igor waves. The result of the call to DateTime also needs to be stored in a wave. Then you can display GasA vs timewave.

Perhaps if you zip your code and attach it here we can be of more help. If the code is voluminous, it may be best to create a small example.

John Weeks
WaveMetrics, Inc.
support@wavemetrics.com

November 16, 2015 at 10:50 am - Permalink