"write to measurement file" specify column names

[tokashila]

Has anyone found a solution to this problem?? It seems like you need a "Set dynamic data attributes" express vi for EVERY signal. It does allow you to change the "signal index" from 0, 1, 2 etc, but you can't specify the name for each index. I have about 20+ Different signals that I am logging so having 20 of these express boxes will be a hassle.

If I find a solution I will post.

Thanks in advance!

~Ryan J. 

[Dennis_Knutson]

Of course it allows you to specify a name. And all that you have to do is place a single function inside a for loop and pass in an array of names.

[Kaaji1359]

Sorry for bringing up an old thread, but I'm having quite a bit of trouble trying to do this.  

Currently I have 2 inputs, a "Water Exit" and "Water Inlet" (this will soon be 15 inputs so just trying to do this the most optimal way possible).  I combine those into "Build Array."  If I output this to "Write to Measurement File," then I get a timestamp with "Untitled" and "Untitled 1" as others have said.  

- If I use "Set Dynamic Data Attributes," the timestamp disappears and goes to 0 or 1.  I'm not sure how to fix this.  

- I'm pretty new to LabVIEW and am not sure how to use the "Set Dynamic Data Attributes" inside a For loop.  I've currently placed a constant array of 1 and 2 for "String Index" and a string array of Water Exit and Water Inlet into "Signal Name," but when I try to connect "Signal Out" with the "Write to Measurement File" Signal, it outputs an error.  

A picture would be fantastic if anyone could provide.  Thank you for your help.  

[Kaaji1359]

Just thought I'd mention that I solved the timestamp issue.  However the "Set Dynamic Data Attributes" function inside a For loop is still giving me trouble.  Thanks.  

[Greg-H]

Hi,

What is the error you are seeing?  Do you have auto indexing for the tunnel out of the for loop turned on or off?

Regards,

Greg H.

[Dennis_Knutson]

This was a duplicate post.

[Kaaji1359]

Figured this thread was dead so I ended up making a new post.  Thanks for your reply though.  

It ended up being an indexing issue as well as changing to shift registers.  

[apacc]

Here is a snippet of what this looks like - I had an issue with this, and figured this would be good for future users.

I did note that I had to use a bit of trickery (1-D array of scalars, most recent value) to make the output file only contain *one* line of data in my loop.

Here is a screen shot of important pieces; a static 1D array of strings, and then the 'for' loop with Set Dynamic Data Attributes inside, and a shift register.

One thing that I haven't figured out - how to make a SubVI out of the loop; when I try doing this, I can't figure out how to create the data pipe coming in (that usually is the output of 'merge signals' or the DAQ Assistant.

[afrowizard]

Hi Apaac,

What exactly are you having trouble with when making the subvi?  Can you not just specify the output of Merge Signals as one of the input terminals?

[apacc]

The issue is that I don't recall/know how to make a Front Panel Dynamic Data Type (feeding into the blue pipe). If I simply right click and create a control input, I get a Numeric Double, which isn't what I need. I'm sure I'm missing something obvious... A