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Does Matlab use Cooley Turkey algorith for their FFT implementation?
I am trying to figure out if Matlab fft uses the Cooley Turkey algorithm, if yes could someone please direct me to the source, i...
11년 초과 전 | 답변 수: 1 | 0
1
답변질문
Why is that when i change my phase angle, the amplitude changes in sin and cos functions in Matlab?
I am doing simple tests trying to get back the amplitude and phase angle from fft, when i have x = A*sin(2*pi*t*f) + B*cos(2*...
대략 12년 전 | 답변 수: 1 | 0
1
답변질문
Need some advice conderning best way to learn FFT and FFT related topics in a timely manner...
Hi all, I am a Phd student in Mechanical Engineering. I have barely ever been introduced to Fourier Transforms and basically ...
12년 초과 전 | 답변 수: 1 | 0
1
답변질문
How important is it to use power of 2 when using FFT?
Here is the problem. I have a 2D array of data, first column represents the time data and the second column represents the s...
12년 초과 전 | 답변 수: 1 | 0
1
답변질문
Given an array of data, is it necessary to use FFT to get the amplitude?
Hello all, I am given an array of data, first column represents the time data and the second represents a sin wave date (usin...
12년 초과 전 | 답변 수: 1 | 0
1
답변질문
Why do I get the wrong phase after I apply FFT to my sinusoidal?
I have a function x = A0*(1+sin(w*t + phi)); all the variable are known. The time vector is provided also. When I take a vecto...
거의 13년 전 | 답변 수: 0 | 0
0
답변질문
Why do I get a phase = 0 when I add a constant to a sinusoidal wave?
Hi everyone, say you have x = A*sin(wt + phi) + A0 where A0 is a constant. When I do fft on x and try to get the phase, I alwa...
거의 13년 전 | 답변 수: 1 | 0
1
답변질문
Does fft() always require 2^n sample points?
Hi, Does FFT always require 2^n? why is that? Thank you.
거의 13년 전 | 답변 수: 1 | 0
1
답변질문
Why do my amplitude become wrong when I vary the frequency from int to double?
So I started with this code: A = 10; B= 17.6; C=2; D=11.2; phi1 = 2; phi2 = 5; phi3 = 1; ...
거의 13년 전 | 답변 수: 1 | 0
1
답변질문
Why is the FFT of a constant returns 0 for the angle?
Is there an explanation to this? Thank you in advance.
거의 13년 전 | 답변 수: 2 | 0
2
답변질문
Getting the amplitude back from FFT, how to ?
Hi everyone, I have a wave that is a sum of sines and cosines: x = A*sin(wt * phi1) + B*cos(2w*t + phi2) + C*sin(2wt +phi3) ...
거의 13년 전 | 답변 수: 2 | 0
2
답변질문
Getting the magnitude of FFT of a sine wave
I am new to fft and a bit confused about the magnitude. This is what I have A =1; t = 0:0.01:1-0.01; x = A*cos(2*...
거의 13년 전 | 답변 수: 1 | 0
1
답변질문
Phase lag from fft, is it the actual lag?
Hello, So basically I am applying a sinusoidal forcing function to a system. Which means, since my forcing function is a sin ...
거의 13년 전 | 답변 수: 1 | 0
1
답변질문
How to use sampling frequency concept when dealing with an array of sinusoidal data?
Hello all, So first I was getting myself used to Matlab FFT, for example I would do the following: clc fs = 4; t = 0:1/f...
거의 13년 전 | 답변 수: 0 | 0
0
답변질문
How to find the phase lag between a sinusoidal input force and the response?
I have a system that is forced by a sinusoidal function with specific amplitude, phase and frequency. I get a deformation of sin...
거의 13년 전 | 답변 수: 0 | 0
0
답변질문
Loss/storage modulii for spring mass damper system, how to?
Hi everyone, I am trying to find the effect of varying the spring constant and the viscous damping coefficient have on the sy...
거의 13년 전 | 답변 수: 0 | 0
0
답변질문
Not getting the correct phase using fft, code posted
Hi everyone, I am trying to extract the correct phase angle from a forced damped harmonic oscillator using matlab ode45() fun...
거의 13년 전 | 답변 수: 1 | 0
1
답변질문
Geeting phase of simple sin wave using FFT
Hi everyone, first thanks a lot in advance. Second, I am brand new to using FFT thus please forgive my basic questions. Say I...
거의 13년 전 | 답변 수: 0 | 0
0
답변질문
How can I show that the matlab IFFT is accurate enough?
I have no experience with fft and ifft and I just started using them. First I was asked to simulate a forced damped harmonic sys...
13년 초과 전 | 답변 수: 1 | 0
1
답변질문
BLAS1 ddot function for matrix matrix multiplication...
I need to do the Cij = Aiq * Bqj, where A and B are matrices that are stored column wise and that do not necessarily have the sa...
13년 초과 전 | 답변 수: 0 | 0
0
답변질문
Using FFT, how to extract the original spring constant and viscous constant?
Hello all, I modeled a Forced damped harmonic oscillator with a specific spring constant k and viscous constant c. After I model...
13년 초과 전 | 답변 수: 0 | 0
