Area Under the Curve -- INTEGRATION

*URGENT

Hi,

I am using the NI DAQ USB 6008 as my data acquisition tool. My task is to get the signal
from a source and make the AVERAGED FFT of the signal and INTEGRATE the FFT
throughout specific limits.

I have been trying to use the TRAPZ function for the integration and here is the code:

area = trapz(f,100*abs(fft_average(1:nfft/2)))

However, i think trapz integrates the signal as a whole.
I would like to put limits in the integration and get the area within that limit. I tried to use
"QUAD" but I'm not sure on how to make a FUNCTION using the acquired signal from the
DAQ. Since the examples that I have read made a function of sine waves and such, but no
other examples for data acquired from a DAQ.

Hoping for your suggestions. I cant seem to find a solution for this.

The code is for my thesis.

Thank You. Start a New Thread

Hey, not exactly sure. but can you possibly just remove the signal that you don't want then run the TRAPZ again on the reduced size ?

just shooting bandage solutions :)

*URGENT
>
>Hi,
>
>I am using the NI DAQ USB 6008 as my data acquisition tool. My task is to get the signal
>from a source and make the AVERAGED FFT of the signal and INTEGRATE the FFT
>throughout specific limits.
>
>I have been trying to use the TRAPZ function for the integration and here is the code:
>
>area = trapz(f,100*abs(fft_average(1:nfft/2)))
>
>However, i think trapz integrates the signal as a whole.
>I would like to put limits in the integration and get the area within that limit. I tried to use
>"QUAD" but I'm not sure on how to make a FUNCTION using the acquired signal from the
>DAQ. Since the examples that I have read made a function of sine waves and such, but no
>other examples for data acquired from a DAQ.
>
>Hoping for your suggestions. I cant seem to find a solution for this.
>
>The code is for my thesis.
>
>Thank You.
> Start a New Thread