topic Re: data displayed from a spreadsheet not correctly in LabVIEW

data displayed from a spreadsheet not correctly

remapears — Thu, 23 Jun 2016 22:30:53 GMT

Hello,

I'm trying to read the content of a spreadsheet (matlab variable) in labview using read from speardsheet VI.But the problem is that when i display the data (using the polymorphic VI double) I get an array containing 2, 1 etc.. but the correct values should be 0.026855000000000 (via Matlab)..

I'm using this data as an input for a matlab algorithm (.m file using matlab script) , since i get a different result implementing the same .m file and input in using labview than using matlab, i thought that maybe the problem is the input data..
Here is the code

Re: data displayed from a spreadsheet not correctly

altenbach — Thu, 23 Jun 2016 23:13:51 GMT

Try to use %f instead of %d (%d is for signed integers)

(...or just leave the format and # of rows unwired. The defaults are OK!)

Re: data displayed from a spreadsheet not correctly

altenbach — Thu, 23 Jun 2016 23:14:20 GMT

If you need more detailed help, attach the data file (or a smaller version of it) and the actual VI.

Re: data displayed from a spreadsheet not correctly

Bob_Schor — Fri, 24 Jun 2016 01:26:53 GMT

Pictures are pretty useless -- we cannot "inspect" them, we cannot "execute" them, and they are frequently "incomplete" (a small piece of the puzzle). I'm sure there is a problem in your code, but would need to see your code, so attach your VI. Also, since the problem involves reading and parsing a data file, attach an example of the data file. With these two things to guide us, you should get a quick (and correct) response.

Bob Schor

Note that Altenbach just said this -- I'm just a poor echo ...

Re : data displayed from a spreadsheet not correctly

remapears — Fri, 24 Jun 2016 08:35:43 GMT

Hi there, thanks for your replies .. Okay I attached two files (Matlab variables saved as ASCII) that I want to load to the VI and get the correct classification (i.e: h1_Healthy as (in french) healthy gears, healthy bearings, healthy shaft (engrenages sains, roulements sains et arbres de rotation saines ) and h4_Healthy_F_F as Healthy gear, faulty bearing and faulty shaft (engrenages sains, roulements defectueux et arbres de rotation defectueuses) ) ..
For your information, the VI contains the MATLAB script of some classifiers (3) that predict the class of 3 component of a gearbox (gears, bearings and shaft). And since the data that they (classifiers) learned on are the same I'm trying to load, the percent of prediction should be 100% for every correct class, the problem is for gears the percent of the correct classification is only 66% meaning that one classifier thought that the gear is faulty (for h1_Healthy) .., you can see the same problem for the second variable..
I hope this time the idea is clearer..Thank you for your time and consideration.

The reason why I didn't want to put up the vi and all, because it wouldn't work on your computers because it needs so many things like other variables, modules and most of all MATLAB installed..

Thank you for your time and consideration.

Re : data displayed from a spreadsheet not correctly

altenbach — Sun, 19 Apr 2026 16:35:33 GMT

Your problem is that each line in the file contains extra speaces,

All you need is "read lines" (see details here), then convert to DBL, e.g. as follows.

(You ave many very questionable code constructs, for example:

None of your value proerty nodes (bottom left of diagram) are needed, just configure the VI to clear indicator when called (execution option). Your property nodes also execute in parallel to the writing to the indicators, thus you can have a race condition and whatever writes last wins. You don't guarantee that the real data writes last.. I am sure you "pyramid" of case structures could be eliminated completely. Try to avoid overlapping and hidden wires. You string concatenation could be replaced by a simple formatting operation. Your little FOR loop does not do autoindexing on the output, thus all you get is the last value, a 2D array with a single element. etc.)

Re : data displayed from a spreadsheet not correctly

remapears — Fri, 24 Jun 2016 15:06:49 GMT

Hi there,

Thank you for your reply, I have tried using the VIs you told me, but I still get one value (2) instead of an array of numvers like 0.002458 etc..

Concerning the other hint you gave me, I'll try to implement them to have a cleaner code.. thanks !

I should tell you that the file i'm trying to import was exported from matlab using the function save ... ascii

Re : data displayed from a spreadsheet not correctly

altenbach — Fri, 24 Jun 2016 15:08:57 GMT

Then show us your new code. Did you really wire a -1 to the number of lines as shown? Did you right-click the file read to "read lines"?

What language is your OS? Does it use e.g. comma as decimal delimiter?

Re : data displayed from a spreadsheet not correctly

remapears — Fri, 24 Jun 2016 15:09:51 GMT

Yes i did... the output of the read lines VI is a scalar..

Re : data displayed from a spreadsheet not correctly

altenbach — Fri, 24 Jun 2016 15:22:23 GMT

@remapears wrote:
Yes i did... the output of the read lines VI is a scalar..

No, you did not! See the different look of the file IO?

You need to right-click the file read and select "read lines".!

(currently you are reading the file a a single long scalar string. Once you read lines, you get an array of strings, one element per line)

Re : data displayed from a spreadsheet not correctly

remapears — Fri, 24 Jun 2016 15:27:32 GMT

wow i didn't know the reason for the different looks.. 😛

Okay so I did that and the results in strings and in double are attached (the picture)..

Apparently, the strings show a more accurate value, than those in double (no change) but still the values are not 2.98... it's 0.00298..

Your help is very appreciated!

Re : data displayed from a spreadsheet not correctly

altenbach — Fri, 24 Jun 2016 15:40:06 GMT

The values in the file are e.g. 2.6855000000000000e-02, which is the same as 0.026855000000000000. (make your string indicators wider to show the entire number!)

You still have not told us about the decimal delimiter setting in your OS. If your numbers typically display with a comma instead of a decimal point, you need to correct for that, e.g. by wiring a FALSE to the top of fract/exp string to number.

You can change the formatting of the numeric indicator to anything you want (e.g. exponential format, number of digits shown, etc.)

Re : data displayed from a spreadsheet not correctly

remapears — Fri, 24 Jun 2016 15:42:36 GMT

Perfect!

I wired the false constant to that VI and changed the display formating and I got the correct display of the double array 😄

Thank you very much! 😄