Please help resolve this math probelm in labview?

[detech]

I try to use fft and ifft to make a filter, to remove some frequencies and then convert to time domain. I have problems to do it. To make it simple I attach a lv 2009 example, which has two component 10 hz and 15 hz input.

Can you help me in removing 15 hz after FFT and then convert with IFFT. Just to check if only 10 hZ signal left after IFFT.

If you can give me an example like this, my problem will be solved.

Thanks

Liming

[detech]

I try to use fft and ifft to make a filter, to remove some frequencies and then convert to time domain. I have problems to do it. To make it simple I attach a lv 2009 example, which has two component 10 hz and 15 hz input.

Can you help me in removing 15 hz after FFT and then convert with IFFT. Just to check if only 10 hZ signal left after IFFT.

If you can give me an example like this, my problem will be solved.

Thanks

Liming

[smercurio_fc]

Please stop asking the SAME question multiple times.

This is the third thread you've started asking the same question. This is very irritating, and does not get you help any sooner.

Original thread.

Moved to this thread. <--- Probably the best place to have discussion.

[detech]

I bough NI cards, labview, and paid service. Can I post my question and get help?

Did my question answered so far?

[strong@ni]

If you want to do the filtering in the frequency domain, you can just set the 15th element after the FFT to 0, as shown by the picture attached:

[PhillipBrooks]

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@detech wrote:

I bough NI cards, labview, and paid service. Can I post my question and get help?

Did my question answered so far?

---

The software boards are NI product users helping other users. NI employees do monitor and often answer your questions, but there is no guarantee of service when using the discussion forums.

If you have a specific question that requires a timely response, you can formally enter a help request where an NI engineer will respond and take responsibility for answering your question(s).

NI employees can be identified on the discussion boards by the blue color of the bars below the user name. You and I (users) are in gold. You will see various shades of blue and gold that indicate the number and quality of the answers provided by that user.

To ask an NI for support, see this web page:

http://sine.ni.com/apps/utf8/nicc.call_me

Since strong@ni is an NI employee and has attempted to answer your question, I would suggest that you continue working on your problem here in this thread.

[smercurio_fc]

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@Phillip Brooks wrote:

NI employees can be identified on the discussion boards by the blue color of the bars below the user name.

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Unfortunately, while it's true that NI employees have blue bars, the reverse is not always true. The forum software will sometimes misidentify someone as being an NI employee when they're in fact not. I've noticed that in general NI employees indicate they work for NI with their signature. Probably a company policy.

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@detech wrote:

I bough NI cards, labview, and paid service. Can I post my question and get help?

Did my question answered so far?

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The point of keeping the discussion in one place is to help you, not to hurt you. As I've explained in the other thread, it's counter-productive to ask the question multiple times. Nobody will know what has been suggested and what you've tried. I know from your point of view you want your question answered, but this doesn't help. It's been proven many times that it doesn't help.

As Phillip noted, if you want direct NI support, and you are not satisified with the help that  volunteers are trying to give you (and you apparently don't seem to appreciate), you need to contact NI directly, not post a question in a public forum. While NI employees monitor these forums, there is NO guarantee of support, and this is explicitly stated by NI.

[detech]

Thanks, I got what you said.