how fit data into dynamic data?

[Thiago Bach]

Hello,

I'm having problems when i want to convert the data that i adquired using VISA to dynamic data. The Dataset consist of one row/column with relative time stamps (elapsed measurement time), and up to 30 channels of data. How do i do this?

Thank you for the help

[srikrishnaNF]

Hi bach,

 Have you tried using toDDT express vi...

Thanks and regards,

srikrishnaNF

[Thiago Bach]

Yes, I've tried, but with no sucess. my data looks so: (in a spreasheet)

time  ch1  ch2  chn

  1     0.1  0.2  0.5

 3.5   0.2  0.1  0.2

The dynamic data does not diferenciates time stamps from measurement values... And as my time interval isn't constant, so i cannot (or don't know how ) use Waveform data type.

 thank you!

[Thiago Bach]

I can separate X from Y, but I'm not able to analyse it with any signal prossesing component (like amplitude & levels.vi)

Thank you!!

[Peter_Schutte_NINL]

Hi Thiago Bach,

May I ask why you want to convert the VISA data to the Dynamic Data Type? Wouldnt it be more effective to do it otherwise?

Can you post your program here (including some comments on what you exactly want to do), so we can have a closer look at the thing you're doing, and how we can help you in it?

Thanks in advanced for posting!

Regards,

Peter S

[Thiago Bach]

May I ask why you want to convert the VISA data to the Dynamic Data Type? Wouldnt it be more effective to do it otherwise?

I want to convert it to dynamic data so i can use tools like Express XY plot. I also will be able to use all the express signal analysys tools.

Can you post your program here (including some comments on what you exactly want to do), so we can have a closer look at the thing you're doing, and how we can help you in it?

The main application form is GPIB READER.vi

You can see that i've two waveform charts that i'm using to display the adquired data. But the problem is that it does'nt takes in account the time stamp associated with each reading.

Now the time stamp is dissociated in each component (year, month, day...) I could treat it to get a elapsed time factor that would be the X in the plot), but i don't know how to do this, sice i can change the number of channels!

Thanks in advance for your help

Thiago Bach

Message Edited by Thiago Bach on 05-06-2010 08:41 AM

[Peter_Schutte_NINL · Accepted solution]

Hi Thiago Bach,

If you look at your code, the best way to proceed is to create a waveform datatype of your data. You can do this by using the Build "Waveform.vi". Here you will find what the help file says about this function.The T0 data format is the regular Timestamp data format (for example generated by the "Get Date/Time in Seconds.vi".

The waveform data type can be directly inputted on the Waveform Graphs.

If you have any additional questions and / or remarks, let me know.

Best regards,

Peter S

[Coq_Rouge]

You should stay way from using Express VIs. They do you now good. And a beginners very often make a code mess by using them. You will be far better of by using traditional Labview. And not some flimflam that NI have glued ontop of Labview using very cheap glue. If you go to toolbar and help, and select example finder. You can search for examples. Just type in xy in search field and you will find many examples. Then I started using Labview I learned a lot by searching in the example database then I was stuck or in doubt. By the way always have concept help on then using Labview (ctrl+h). This and example finder is your best Labview helpers 

[Thiago Bach]

Thanks for the answers!!

Peter, The main concern about the waveform.vi is that i dont have a fixed time interval dt. Every reading can have a different interval. Still possible to use the waveform format?

And Rouge, i've allready heard about the desavantages of the express vi's (even from guys from NI). But when you just want to evaluate the data adquired, its a important tool! But for sure, with some extra time, the result of doing "oldschool" labview is for sure better!

Thanks again for the attention,

Thiago

Message Edited by Thiago Bach on 05-11-2010 08:33 AM

[Coq_Rouge]

---

Thiago Bach wrote:

Thanks for the answers!!

And Rouge, i've allready heard about the desavantages of the express vi's (even from guys from NI). But when you just want to evaluate the data adquired, its a important tool! But for sure, with some extra time, the result of doing "oldschool" labview is for sure better!

---

Inside every Express VI you will find traditional Labview. Select the Express VI then right click on it and select open front panel. Then dive into the code until you find the core function some levels down. For the XY Express VI this is the code. Not very impressive I would say. I have sometimes used a express VI as base for for code. But of course peeled away all unnecessary and awkward coding inside