Array manipulations...
Hi
I would like some help with array manipulation
I have multiple files (1000 text files) with 5 columns each and 20,000 rows. The first row of each file has a header that labels the columns.
I would like to be able to read each of these files, pull out colum 3 from each file and then build these into a new 2D array. It would be nice if they also had their corresponding header labels. So then I would end up with the new 2D array containing 1,000 columns (corresponding to column 3 of each of my 1000 files) with 20,000 rows plus a first row with the header labels.
I would also like the option to in future select column 2 for example, or column 5; plus I would also like the functionality to allow me to perhasp pull out more than one colum, e.g. colum 2 and 3, before we build the new array.
I hope I made some sense and that someone can help. Thanks you
Oh nuts!
While I was trying link those posts to give a heads up to the forum I had a sinking feeling that I was going to get it all wrong.
I need to be more mindful of my feelings ....
cheers
David
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Hi
When I run:
app.selection[0].geometricBounds = [0,0,10,10];
everything works as expected.
I only want to change the width so I tried:
app.selection[0].geometricBounds[3] += 10;
or
app.selection[0].geometricBounds[3] = app.selection[0].geometricBounds[3] + 10;
nothing changes and no error message appears.
I solved it in the following clumsy way eventually:
a = app.selection[0].geometricBounds[0];
b = app.selection[0].geometricBounds[1];
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So it finally kind of works but it leaves me scratching my head. Is this really the way to do it?
Thanks for clarification
wellerI would do it this way:
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The point is that because the property is an array, you must set it with an array -- if you try to manipulate a member of the array, what happens is that ExtendScript creates a temporary version of the array, manipulates that and it is left hanging out there with no effect.
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Hi :-)
I've RTFM'd but couldn't find the answer so here goes.
I'm using Java syntax and would like to manipulate my array like so:
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I would like to comment something.
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I would like to be able to manipulate some data (columns 2 and 3 of txt file) that I am collecting as a function of time (column 1 of txt file).
Right now, as the VI is running, this data is being plotted on a waveform chart and saved to txt file.
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Column 3 - As is.
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It's not incredibly critical that the data manipulation occur in real-time...it can happen after the file has been written if necessary. The final graphical result should look like the attached jpeg.
Thanks in advance for the help - I'm a little uncertain about array conversion, unbundling, etc. nevermind the mathematical differences and averages that need to be obtained.
Meredith
Solved!
Go to Solution.
Attachments:
Example Spectrum.jpg 36 KB
Example Spectrum Data.txt 323 KBhello,
i tried to make what i understood , see if it make sense
few textual details in vi, two jpg attached in case your 're not LV8.6
look at xy result to see if that talk to you , not for me
Best regards
Tinnitus
CLAD / Labview 2011, Win Xp
Mission d'une semaine- à plusieurs mois laissez moi un MP...
RP et Midi-pyrénées .Km+++ si possibilité de télétravail
Kudos always accepted / Les petits clicks jaunes sont toujours appréciés
Don't forget to valid a good answer / pensez à valider une réponse correcte
Attachments:
spectrum.vi 21 KB
spectum_code.jpg 131 KB
specto_xy.jpg 123 KB -
I need to add several 512 by 512 arrays and do arithmetic manipulations on them(multiply, divided, etc). these arrays are 16 bit unsigned short and I am afraid that some of the entries will overflow as I add on more arrays, how do I get around this problem?
Can a computer learn how to program?You could convert them to DBL at the beginning, using the conversion bullet.
(For division the output will be DBL anyway)
Message Edited by altenbach on 12-16-2005 09:39 AM
LabVIEW Champion . Do more with less code and in less time . -
How to manipulate arrays using case statements and boolean conditions?
In the vi that is attached I am trying to compare two values in two different arrays and delete the value that is equal to zero. The values of each array are rounded to the closest integer. Then I attempted to apply the ">0" boolean as the condition for my case statement, but I am getting an error. Any tips on manipulating arrays with case statements?
Attachments:
Patient Movement Monitoring.vi 141 KBThank you!!! that was a huge help. I don't think I need the case structures at all. The next part of the code compares the 4 values in the array.
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Only one of the "AND" booleans will return true for each index. Is there a way to initialize another array of outputs 1-4 depending on which AND returns true?
Attachments:
Patient Movement Monitoring.vi 144 KB -
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Attachments:
average problem.JPG 205 KBFirst off, I didn't create this VI, so I am really confused as to what is going on. So I agree. And the picture was just to show where I am starting from. My ideas haven't been implimented, for reasons such as...I don't know much of what I'm doing. I know it's a pain when someone as new to labview as I am posts questions. The person who worked on this VI moved and it's part of an ongoing research project. So a newbie like me was thrown into it, and it's a steep learning curve! The data that is split out of the DAQmx (that just goes down to the file) is what I need to average. I expected a 1D array of just one data point per channel to come out of the DAQmx but I get a 2D array. So I am really confused. Thanks for looking at it anyway. I don't think I can really say much more other than the basics that I just need to take that 2D array and average the oversampled data. One application is that we are taking temperature data and there is a lot of noise so we need to average those channels. And since the other channels will be used eventually, we just wanted to average each channel, and throw it back into a 2D array.
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thanks again,
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Its "The only IDE you need."
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Arrays of arrays or list of arrays?
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Figured it out right after posting the question...
Well newbies are newbies, eh?
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