How do I select more then one channel to view in tdms file viewer graph panel

[cjp1]

I have a TDMS file that I can view with the labview 2013 TDMS file viewer and I can select one signal out of 15 signals to view on the graph panel. however I would like be able to look at 2 or 3 signals

on the same graph but can't seem to be able to select more then one signal at a time. Is there a way to select more then one to view?  

[deppSu]

Generally, TDMS file viewer doesn't support viewing multiple independent channels in a graph. You can only view all the channels of a group by seleting the group.

[Hooovahh]

I've modified the TDMS viewer in the past to allow selecting multple channels.  It's a little bit of a pain because the tree control in the viewer only allows you to select one item.  You have to edit the tree to allow multiple items.  Now your selection is an array instead of a scalar.  This means the rest of the code has to be updated, and the references to the tree in subVIs need to be updated.  Not impossible but it takes some time.  Alternativly open it in Excel with the free add-in then you can select the two columns you want and insert a graph.  Not as simple for the user but using Excel, which users should be familiar with might mean users need less training on data files.

[Sman29]

Hooovahh,

Do you have an example of the TDMS with multiple channel selection?

Thanks!

[crossrulz]

I recommend just using Scout.  It was developed by Signal X and it works beautifully.  They do have a free version you can use.

[Sman29]

We do have Scout, but for my project we need to be able to select multiple channels through LabVIEW. I am fairly new to LabVIEW so any examples of this would be greatly appreciated!

[Hooovahh]

---

@SteMob wrote:

Do you have an example of the TDMS with multiple channel selection?

---

Nope, just the description I mentioned earlier.  Change the control to an array instead of a scalar tree, and update the code to select multiple channels, it isn't that difficult, post your code if you are having any specific issues.

[Sman29]

I think I may have figured out an easierish way. In the File Tree: right-click-->Selection Mode-->0 or more items. This allows multiple selections of the tree siblings. However, it changes the type to array as previously stated, so you will have to update the code paths and such, but that seems to be a more intuitive way to get there.

[Hooovahh]

---

@SteMob wrote:

I think I may have figured out an easierish way. In the File Tree: right-click-->Selection Mode-->0 or more items.

---

...you know that's what I was trying to describe.

Anyway I went searching in the depths of old files and found some code that I made that allows multiselect in the TDMS viewer.  It is old, and the newer versions of the TDMS viewer (ones shipped with LabVIEW) probably have some improvements and better code documentation.  I also don't know how well it works, I think it was from a time when the TDMS file format only had 1.0 so you may need to update a few constants.  But it is probably is a decent start.

[Sman29]

Great stuff, thanks! I found 2 of the cases have errors in your program (same cases I was having errors on my program). It's the 3rd and 4th cases ("File Contents" and "Settings"). It looks like the Get Channel List is the VI that is having problems. Most of the errors are different terminal errors or something along those lines, but I'm not really sure how to go about fixing all of them. Any ideas on how to fix them? It may not pull up errors on yours...