How to generate a plot of 450,000 data points vs. time for 30 minutes?

[bilk]

I am trying to plot data acquired from several pressure transducers. The shape of the graphs is similar to a sine wave with a frequency of 1/2 Hz but not as smooth. I need to plot the data for as long as a half hour or as short as 20 seconds and it must all be visible at the same time. I have tried to use a waveform chart but the chart will only display the most recent 4 seconds worth of data. Any ideas about how to squeeze all of that data onto one chart?

[Sandeep]

In the longest duration (half an hour), how many data points do u have for one transducer? Such how many transducers do u intend to display on a single chart at the same time?

[bilk]

Sandeep,

For a half-hour test, I would have 450,000 data points per channel. There would be up to four channels, three pressure transducers and a thermocouple.

[cin]

Increase the chart history length by right click on the waveform chart.

Ho-ming


bilk wrote in message news:<5065000000080000009FB40000-1068850981000@exchange.ni.com>...
> I am trying to plot data acquired from several pressure transducers.
> The shape of the graphs is similar to a sine wave with a frequency of
> 1/2 Hz but not as smooth. I need to plot the data for as long as a
> half hour or as short as 20 seconds and it must all be visible at the
> same time. I have tried to use a waveform chart but the chart will
> only display the most recent 4 seconds worth of data. Any ideas about
> how to squeeze all of that data onto one chart?

[Sandeep]

Hi,
I created and I am attching a simple (basic) program that
-displays 4 channels on same charts.
-chart can store history of 500,000 points per channel

To edit history length, right click on chart and go to bottom of menu (as suggested ny Homing)

If you wish, you can change the history length in runtime(using chart property node). I can modify this program a bit if you want demo of it.

Let me know if this helps
ciao-

[bilk]

Sandeep,

Thank you very much for your quick response. Isn't funny how some things can seem so dificult until we know the answers?

Thanks again,
Bilk