Can someone help me please? (convolution)

[Cpow]

Hello everyone,

I am new to these forums and also new to LabView. I am currently running LabView 8.0 for a class that I am currently attending. I think LabView is a great program and I have a lot of potential on it; however, I am having a really difficult time trying to program something.

My teacher didnt exactly teach us how to do anything on LabView, he basically gave us the program and 3 hours to learn it. For an assignment I have to prove convololution on two discrete signals using the built in convolution VI in LabView. I completed this part because it is a relatively simple task. Now I have to Write my own convolution VI and use it to convolute the same two signals.

Now I am a complete novice when it comes to LabView and programming in general. I have no idea how to begin this nevermind actually starting to write a code for convolution. I'm honestly not sure if anyone would know what im talking about but i see a lot of intelligent posts on this forum and i figure perhaps someone could help me out.

If this seems easy to anyone could you possibly help me get started? Im terrible with programming and with LabView, I just need a little help.

Thank You

-Chris

[crelf]

My teacher didnt exactly teach us how to do anything on LabView, he basically gave us the program and 3 hours to learn it

Nice! Post what you've already done with an explination and we'll try to help.

(the coffee was actually excellent this morning - Panera cappacino - mmmmmmmmmm )

[Cpow]

Well basically what i have to do is create my own convolution VI and use it. Its probably really simple but i just dont know how to get started.

I attached my work so far which includes me using the built in convolution VI in labVIEW 8.0 on 2 simple signals. Basically what convolution does is it takes the second signal, flips it around the x axis, then moves it to the right. Whenever the signals are overlapping it multiplies them together. It's hard to explain i know.

This is a really simple explanation of how convolution works. Now all i have to do is create my own convolution VI, but i really dont know where to get started. Im looking into it and ill update whenever i get any idea of how to do it.

Thanks,

p.s. I also dont know how to attach thumbnails :/ .. How do i do that?

-Chris

Download File:post-5351-1151280875.vi

[Kurt Friday]

Well basically what i have to do is create my own convolution VI and use it. Its probably really simple but i just dont know how to get started.

I attached my work so far which includes me using the built in convolution VI in labVIEW 8.0 on 2 simple signals. Basically what convolution does is it takes the second signal, flips it around the x axis, then moves it to the right. Whenever the signals are overlapping it multiplies them together. It's hard to explain i know.

This is a really simple explanation of how convolution works. Now all i have to do is create my own convolution VI, but i really dont know where to get started. Im looking into it and ill update whenever i get any idea of how to do it.

Thanks,

p.s. I also dont know how to attach thumbnails :/ .. How do i do that?

-Chris

Hi Chris

First, I admire how you have asked for help and you have had a really good shot at solving your problem. I can provide a little hint here. You are using express vi's, however you can convert an express vi into a regular vi by simply right clicking on the express vi and selecting "Open Front Panel", the express vi will then be converted, take a look inside, you will then see subSignalProcessin.vi, take a look in there that will help you.

Also if you want to attach an image into your post simply attach the image file and then you will be given a reference which you can insert in your post.

Good luck with it.

[Guest terminator]

If you can describe it, you can implement it (although it might take a while to find the right vis to do it).

I suggest starting your search under the array palette. In particular there is a "Reverse 1D array" vi that should be very useful.

Well basically what i have to do is create my own convolution VI and use it. Its probably really simple but i just dont know how to get started.

I attached my work so far which includes me using the built in convolution VI in labVIEW 8.0 on 2 simple signals. Basically what convolution does is it takes the second signal, flips it around the x axis, then moves it to the right. Whenever the signals are overlapping it multiplies them together. It's hard to explain i know.

This is a really simple explanation of how convolution works. Now all i have to do is create my own convolution VI, but i really dont know where to get started. Im looking into it and ill update whenever i get any idea of how to do it.

Thanks,

p.s. I also dont know how to attach thumbnails :/ .. How do i do that?

-Chris

[Cpow]

Wow thank you so much..

I can understand this much better now .. ill keep going and see what i can do.

thanks alot guys!

-Chris

[Gary Rubin]

Convolution can also be implemented MUCH faster in the frequency domain, using FFTs.

See here.