Writing Waveform data into CSV file

[GerdW]

Hi arpix,

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@arpix wrote:

My only problem is that that every time when i start the project to  creat the curve i would like to create a new csv file and not to wirte the data in same csv file. Could someon help me how shall i do that? 

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When you want a "variable" filepath then you should not use a "constant" filepath!

Why don't you build your path using some parameters (like timestamp) to "create a new file every time"?

There is a BuildPath function in the file functions palette. And there is a FormatIntoString function to format any parameters into a string…

On your image:

• Why do you set the "Y" array of the waveform "Graph created with CSV curves" twice? Do you know what happens with the inputs at this SetWfmComponents function?
• Where is the label of the graph indicator?
• You only save the Y data to a CSV file, but you forget about all the other waveform parameters!? Is this intended/required?
• Why did you mark that BuildPath example with a red cross?

[arpix]

Hi GerdW,

Thank you for replaying me so quicly.

I will try to answer on your quetsions: 

On your image:

• Why do you set the "Y" array of the waveform "Graph created with CSV curves" twice? Do you know what happens with the inputs at this SetWfmComponents function? Answer: I could not find any better solution to compare two Wave form on one graph. Basically 1 wave form is created based on parameters the secound on is reading out one already created csv file. 
• Where is the label of the graph indicator? Answer: Not really sure what do you mean under this?
• You only save the Y data to a CSV file, but you forget about all the other waveform parameters!? Is this intended/required? Answer: Yes. and no. For start i want to solve one problem step by step. But i would like to save two colums of data separated with ",". X is shall be the time and the Y shall be the pressure of the curve. 
• Why did you mark that BuildPath example with a red cross? Answer: I was trying with that something out but i am getting some errors... Not really know how to continue... so that is just a try....

[GerdW]

Hi arpix,

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@arpix wrote:

• Why do you set the "Y" array of the waveform "Graph created with CSV curves" twice? Do you know what happens with the inputs at this SetWfmComponents function?
  Answer: I could not find any better solution to compare two Wave form on one graph. Basically 1 wave form is created based on parameters the secound on is reading out one already created csv file. 

You didn't answer to my question.

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@arpix wrote:

• Where is the label of the graph indicator? Answer: Not really sure what do you mean under this?

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The graph indicator in the middle (just behind the BuildArray node) doesn't has a label.

There shouldn't be any terminals without labels in the block diagram!

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@arpix wrote:

• Why did you mark that BuildPath example with a red cross?
  Answer: I was trying with that something out but i am getting some errors... Not really know how to continue... so that is just a try....

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Which errors did you encounter?

We cannot help until you describe the errors you see!

(And we cannot debug/edit/run images with LabVIEW: when there are problems with your code then you should attach your code…)

[arpix]

Hi GerdW,

Thank you for pointing me some of my problems.

Unortunatelly i was unable to answer you because i am a new on this forum so i could not reply 24h.

Ah, sorry — yes, you pointed out the error I hadn’t noticed. I’ve already fixed it. But some extra explanation would be great from your side. Regarding the two y input. I know that the first is for Y axis. The 2nd Y input was not showed correctly on the graph. what is wierd. 
The graph without a name is the Comparison Graph for the two waveforms. Yesterday I think I managed to find a solution to my problem. Thank you for pointing out the major issues and key points. I still have to work on it.

I’ll take any good advice on what’s wrong and what should be improved.

[GerdW]

Hi arpix,

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@arpix wrote:

Yesterday I think I managed to find a solution to my problem. Thank you for pointing out the major issues and key points. I still have to work on it.

I’ll take any good advice on what’s wrong and what should be improved.

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Improvement:

Simpler way to create your 2D array of time&sample.

(Maybe you need to transpose to get the same CSV file as you get now.)

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@arpix wrote:

The graph without a name is the Comparison Graph for the two waveforms.

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And you still don't give a label for that graph!

I repeat: "NEVER delete labels, you may hide them in the frontpanel…"

Also don't get into the habit of "wiring backwards": try to keep the block diagram on one (FullHD) screen with wires from left to right! (Basic styleguide rule!)

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@arpix wrote:

Regarding the two y input. I know that the first is for Y axis. The 2nd Y input was not showed correctly on the graph. what is wierd. 

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It's not "weird", it's expected!

There is only one Y array in a waveform: writing to that array twice will simply overwrite the first data array…

[arpix]

Hi GredW,

I’ve fixed it now, considering the name (label). Your example is much cleaner and simpler

Thank you!

[LV12]

Hi, 

How are you reading 3 channel current data simulteniously ? Did you use any parallel coding style? 

Is it possible to share the code? 

[arpix]

Hi LV12,

I don’t really understand which part you mean? You mean this? 

 If yes, than this signals are not currents.