I have multiple channel data which is acquired through a single task in MAX. The data is put into an excel sheet. Firstly, is there a way that I can pull specific columns from this excel sheet and use it in a 3D plot function? If yes, how to make the data for the X, Y, Z axes be user selectables?
Thank you very much in advance for the help.
Yes. You can use ActiveX connectivity in LV to read Excel document with Excel API which requires Excel installed on your machine.
Take a reference to "<LVROOT>\examples\comm\ExcelExamples.llb\Write Table To XL.vi". It is an example to write an Excel document. Create the similar code to read an Excel document base on your sheet format.
Thanks for the reply.. What i am trying to achieve is that I should be able to first select any columns from a data file that is created and then use those particular columns for the axes of the 3D plot. Also the axes of the 3D plot should be user selectable and the data on the axes should be able to change according to what is selected. Is it programmatically possible to do this?
Can you please help me with some examples. I am pretty much new to LabView. Thank you in advance.
If you don't know LV you may want to start by poking at the Car example to get an idea what 3D plotting is like.
That should get you started but quoting Ross Perot "The devil is in the details."
Post up your code if you get stuck and supply sample data.
I have attached the VI that I am working on. I got my VI to collect data but the huge structure that I made I think does not work correctly. I am trying to get rid of the headers from the data file that i create and then use the selected columns from the data file using the 'Select Signals' VI for the axes of the 3D plot. And then I try to toggle between in the axes according to the user's wish.
But when I run the VI, it collects data but does not show it on the 3D plot. I can't figure out what is wrong with it. I would greatly appreciate your help. Thank you.
I do not know those Express VI sthingies and on the day before my vacation starts, have no desire to learn about them so I am not going to be of any use to you.
Sorry but maybe someone that knows those exress thingies can help.
Hey ksurdi, this is Paul with Applications Engineering at NI.
I'm not sure I totally understand your questions, but in regards to using Express VIs for writing to measurement files, that is only for simple operations. If you want to start changing up headers and stuff, you will need to start using our more base level functions. These functions give you total control over how your files will be built, and I think will give you what you are looking for. Check out this tutorial for more info: http://zone.ni.com/devzone/cda/tut/p/id/9334
Beyond that, I'm a little confused about the scope of the application. I see you reading from a file and building it into a 3D plot a the bottom, then reading some data, and plotting that on a surface at the top. For the purposes of helping us work with you some, could you change some of those external inputs you are getting into constants in the code, so we can work with the same data you are?
In the mean time, if you haven't already, there is a lot on our Developer Zone about 3D Plots that may be able to help you.