How to plot variables magnitude versus time stamps with samples not evenly spaced in time?

[belford@uol.com.br]

Hi everyone. I need to plot variables magnitudes versus time stamps (date and time) but the time intervals between samples are not evenly spaced. In my area this is called trend plot. I am surprised that Labview does not have a vi for this. The only solution that I found so far is to save the data into a Excel file and open and graph it in Excel as it has this capability to plot anything against anything not being limited to anything like even spaced samples. How to achieve this is Labview? A waveform graph vi would be perfect if it wasn't by the fact that it only works with even spaced samples.

Thanks.

Paulo Siqueira

[Henrik_Volkers]

XY-Graph will do the job, just spend the timestamps 🙂

And you can do it with a chart 😉

[belford@uol.com.br]

Thanks for the answer Henrik, but what you mean by spend the timestamps?

X-Y graphs as far as I know only accept DBL values for X and Y and not timestamps. I would not like to have relative time in seconds or something similar. I really would like to see date and time in the X axis.

Can you help me with a suggestion?

[Yogesh_Redemptor · Accepted solution]

Your requirement is directly possible with LabVIEW.

You can spend time to understood the difference between 'Chart', 'Graph' and 'XY Graph'.

Attached VI is plotting the uneven time samples.

Clue:- Right click the 'XY Graph' -> Properties -> Display Format -> 'X Axis' = Absolute Time

Regards,

Yogesh Redemptor

[belford@uol.com.br]

Thank you very much, Yogesh Redemptor. It worked. My thanks also to Henrik.

Greetings from Brazil...

[germanp]

I couldn't open the VI file because I have LabView 2010 version

I tried to do the samething (I'm not sube about the false case) with XY Graph but it's not be automaticaly updated, and i need necessarily it. I tried to use Chart Graph but the current time is not correct because the sample time is variable.

Does somebody have an ideia?

Thanks in advance