Re: [ferret_users] Re: FFTA

To: Yadidya Badarvada <israeljedidiah@xxxxxxxxx>

Subject: Re: [ferret_users] Re: FFTA

From: saurabh rathore <rohitsrb2020@xxxxxxxxx>

Date: Tue, 5 Jun 2018 10:06:00 +1000

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Dear Yadidya,

Fast Fourier Transform i.e. ffta yields the same unit of the variable as it is the amplitude of the variable for various frequencies. so on y-axis it is celcius to best of my knowledge. But if you make it square i.e. [ffts[var]]^2 then it became Intensity.

you can check this link as well

https://stackoverflow.com/questions/1523814/units-of-a-fourier-transform-fft-when-doing-spectral-analysis-of-a-signal

regards, saurabh

On Mon, Jun 4, 2018 at 9:32 PM, Yadidya Badarvada <israeljedidiah@xxxxxxxxx> wrote:

Dear Ferreters,

What are the units of y-axis when the function "ffta" is used?
If I'm using the time-series data of temperature, then is it "(celcius)^2" or "(Celcius*sec) ?

Regards,
Yadidya.B

REGARDS

Saurabh Rathore

Research Scholar (PhD.)

Centre For Oceans, Rivers, Atmosphere & Land Science Technology

Indian Institute Of Technology, Kharagpur

contact :- 91- 8345984434

References:

[ferret_users] Re: FFTA
- From: Yadidya Badarvada