How do I put a fixed scale of 1 Minute Intervals on the X-axis of a Wavform Graph?

[hova2010]

Hello

I am using a Waveform Graph and I would like to put a set of 1 minute real time intervals on my graph.

My data comes once every 4 seconds, so the 1minute intervals  must be in real time with my incoming data.

So about every 15th data point, I should cross a 1minute marker.

but can anyone tell me how to create these 1 min intervals that would be real time with my incoming data?

thanks

J

[Dennis_Knutson]

I suspect that you should be using a chart instead of a graph. To display time on the x axis, why don't you give the shipping example called Real-Time Chart a look. With a few quick mods, it would look like the image below.

Message Edited by Dennis Knutson on 10-13-2009 02:06 PM

[hova2010]

hello

Im new to Labview, I have tried a Waveform Graph and also Chart.

I have also tried to real time example, but it charts to the second.

How do i just chart to the minute?

J

[Dennis_Knutson]

If you have used the example and can't get it to work, post what you've done. The only modification I made to the example was to set the Offset to 0, maximum to 240 to get a 4 min scale, set the delay to match yours, and turned on the gridlines.

[hova2010]

I cant get the X scale intervals to stay fixed...each time I start my application, the scale moves ??

How can I always get a a fixed set of 1minute intervals?

thanks

J

[Dennis_Knutson]

Change the formatting back to relative time and use 0 as the offset (as I said) if you want the time to start at 00:00:00.

[hova2010]

I would like to start at the same time as the windows PC clock  (hh:mm)

Then starting at that time, I would like to have set 1min intervals  ,e.g  if start was   4:40pm....then I would like to set 4:41pm  4:42pm, 4:43pm, 4:44pm etc as my 1min intervals on the X axis

Can you help with this ?

J

[Dennis_Knutson]

Since you start at random times, I suspect you will have to turn off uniform marker spacing and create an array of marker spacings and write it to the MarkerVals[] property node. See attached

[hova2010]

this is the closest solution i've seen....the only thing is, this test will run for months.

If I follow you correctly, I would have to create a huge array of marker spacings (marker vals)??

Would these spacing continue as the graph advances to the end?

J

[Dennis_Knutson]

No, I don't think the intervals will continue. You may have to use uniform markers. Right now, I don't know if you can get all markers uniformly spaced if you use system time and start at some random moment.