Prepare Fourier Amplitude Spectrum from ground motion record (Peak-Acceleration vs time-period)
Perhaps this — T1 = readtable('india.19911019...at_output.txt'); T1.Properties.VariableNames = {'Peak Acceleration','Time'} ...

29日 前 | 0

Other ways to improve fft amplitude
Another option may be to zero-pad the fft using: Fs = signal_sampling_frequency L = signal_length; NFFT = 2^nextpow2(L) FTs...

29日 前 | 1

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How can I write a set of first order ODEs with two variables?
Try something like this — syms D g m t x(t) y(t) Y dx = diff(x); d2x = diff(dx); dy = diff(y); d2y = diff(dy); DEqn1 ...

Recover signal from single-sided spectrum using ifft
The problem appears (to me) that you are using the absolute value (‘P2’) of the fft result. This essentially discards the phase...

FFT to a simple sine wave
I am not certain what the independent variable axis is (the label is cut off), however if you want a power spectral density plot...

I am recieving an error in creating the solution however it still prints a result.
In the last iteration of the loop, the results are all empty. One way to avoid the error is to test for at least one field to ...

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Solving ODE using laplace
Your code looks correct to me, and when I checked the result with dsolve, its solution agreees with yours — syms t s y(t) Y X ...

Old Matlab example of 1D FFT filter
The only function that I am aware of that might do what you want is the fftfilt function (introduced before R2006a). It require...

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Plot a vector with a given angle against the y-axis
Another approach — thetad = 280; % Desired Angle (Guessing Value) x...

Decreasing bin size FFT options for increased resolution
You can minimise the spectral leakage by windowing the fft (except for a rectangular window, which is the default if no others a...

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Could anyone explain the example provided in thr help for understanding the use of fft?
This calculation of the frequency vector for the displayed Fourier transform is not the easiest to understand: f = Fs*(0:(L/2)...

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Need help in assigning frequency and normalising amplitude to the fft plot
There may be several approaches to your problem. One of them is this — clear all close all clc L=10; n=1.45; c=2.9979e...

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Left and Right side have different elements
You need to subscript ‘t’. Then, it works — t = 0:0.01:4; % Timesteps for robotic arm motion for i = 1:length(t...

Error using Odearguments - vector must return a column
You only have one differential equation, so only one initial condition is necessary. %r_H2= -(-Rds - Rwf - Rh); %Rd = kds*(C...

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I want to change the symbolic variables in my matrix to numbers
Use the fplot function — clear all ; close all; close ; clear syms s Expr = (sin(s)); F1 = int(Expr) syms n expr2 = 1/n ...

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How to remove (or isolate) side peaks except main peak after FFT
Using: NFFT = 2^nextpow2(numel(signal)) and a window function (for example hann) in the fft call could improve the fft result...

Trying to combine two IR spectra where x is wavenumber (cm-1) and y is transmittance (0 to 1), having trouble.
It would help to have the data. The best way is probably to interpolate the longer series to the length of the shorter series...

Perhaps something like this — % Data data = [0.496; % Electrical conversion efficiency 0.426; % Biogas efficiency val...

I'm trying to find displacement from acceleration datas
Your original ac celeration data have a trend, and you are integrating the trend. Use the detrend function tto remove it (alter...

Fitting an anonymous function: Debye Callaway Model
I do not have your data so I cannot run your code. However it is always appropriate to compltely vectorise objective function...

How to Reshape a Matrix into a Cell
Transpose the row vector, call reshape, then transpose that result — syms R11 R12 R13 R21 R22 R23 R31 R32 R33 k = 1; timest...

Curve fit autocatalytic model
if ‘x’ is greater than 1 and ‘n’ is not an integer, the result will be complex. Example — k = rand m = rand n = rand x ...

fsolve function not solving nonlinear equations, I had observed "Invalid datatype. Options argument must be created with OPTIMOPTIONS"; could you assist me, pse
One problem is that fsolve wants the initial parameter estimates as a single vector, and the third argument is the ‘options’ str...

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apply hanning window for signal processing
I do not understand your code, so I am not certain where to suggest adding the hann call in that context. (I specifically do no...

How to assign new variables?
Use the strrep function instead of the if block — jj = 1; dependent_vars{jj} = 'act_per_ha'; jj = 2; dependent_vars{jj} = ...

Latex, sprintf and variable that changes
Your sprintf statement has fields for 3 variables, however you only provide 2. Provide all 3 and it works — i = 1; j = 1; ...

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Why I have the error Genetic algorithm script error no Global Optimization Toolbox ?

I need to plot precipitation data. First, adjust y limits of a stacked plot to accommodate totals for the month. Second, have dates on the x axis.
Convert the table to a timetablee and ‘Column2’ will automatically be plotted as a funciton of the time variable. However I d...

How to get the Z-transform and tf of this function y[n] = 0,5y[n − 1] + x[n] ?
Perhaps something like this — syms n x(n) y(n) z t X(z) Y(z) assume(n>=0 & in(n,"integer")) Eqn = y(n) == 0.5*y(n - 1) + x(...

Finding and integrating peaks in a data array
The findpeaks function will accurately locate the peaks. Integrating them depends on what you want to do. In the past, I have ...