Has anyone written an Import Waveform from Spreadsheet File?

[deserio@florida]

It would be nice to have a vi that can read the files written by Export waveform to spreadsheet file. I realize this is a lot of work, but if you want to be able to use waveforms with a spreadsheet as well as with LabVIEW, the only alternative is to save it twice -- once using Export Waveform to Spreadsheet File and once using Save Waveform to File.

[SachaE]

Hi,
this is simply a case of re-organising the data you're saving. You have the waveform Y array, and you need to append on the dt and t0. Then save this whole array.
Unpacking it is a case of doing it in reverse.
S.

[DonC]

I also want to import a set of data from a spread sheet to create an arbitrary waveform as a drive source.

[parthabe]

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@DonC wrote:
I also want to import a set of data from a spread sheet to create an arbitrary waveform as a drive source.

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What type of file are you having ? If it is .csv or .xls file, you can very well use the VI in the previous post.

Can you explain more of your actual requirement ?

[DonC]

Hi,

I am very new to LabVIEW.  I am primarily a digital engineer with 37+ years of experience and some analog experience.  I started programming uPs in 1972 with the Intel 8008.

I thought that the previous post was for exporting the waveform only, now I have run it and I see that an import is also possible.  I don't quite understand it however.  Apparently the csv file data is Y values only with even steps of X determined somehow.

What I am looking for is the ability to create a spread sheet with X, Y pairs to describe the waveform.  What we are doing is hydraulic impulse testing.  What we need to raise a pressure over a short time, then decrease the pressure, then maybe raise the pressure again to a value, then hold the pressure steady for an extended time, then reduce the pressure back to 0.

Here is a very simple example spread sheet file.  I could easily export the two data columns to a CSV file, and I can organize the spread sheet in whatever way might be easier to work with in LabVIEW.

I appreciate the help.

[Coal_Man]

Hello Don,

Though I don't know how exactly you want to have this data be generated, you can import the data and change this into a waveform fairly simply.  I have attached a VI that opens a CSV file that will plot a waveform of the data.  It assumes that the data is whole numbers and does not linearly interpolate the data.  So the plot has a lot of points that increase or decrease in the period of 1 second.  Though this may not be the perfect code you need, this is a good basis for starting to get your data out and manipulate it.  If you have any questions, please let me know.

[Coal_Man]

Hi Don,

Here is a better example that uses the interpolate function.  I adapted the Interpolate 1D array example.