Star Strider

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Hic sunt dracones! PROFESSIONAL: Physician (M.D.): Diplomate of the American Board of Internal Medicine; M.Sc. Biomedical Engineering: Instrumentation, Signal Processing, Control, System Identification, Parameter Estimation NON-PROFESSIONAL: Amateur Extra Class Amateur Radio Operator; Private Pilot, Airplane Single Engine Land, Instrument Rating Airplane; Gamer NOTE: I do not respond to emails or personal messages, unless they are about my File Exchange contributions. Time Zone: UTC-7 (Standard); UTC-6 (Daylight Savings/Summer)

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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)...

1 hour ago | 0

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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...

10 hours ago | 0

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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...

1 day ago | 0

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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...

1 day ago | 0

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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 ...

1 day ago | 0

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Answered
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...

1 day ago | 0

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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...

2 days ago | 0

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Tornado chart with colormap gradient
Perhaps something like this — % Data data = [0.496; % Electrical conversion efficiency 0.426; % Biogas efficiency val...

2 days ago | 0

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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...

2 days ago | 0

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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...

3 days ago | 0

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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...

3 days ago | 0

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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 ...

3 days ago | 0

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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...

3 days ago | 0

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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...

3 days ago | 0

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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} = ...

5 days ago | 0

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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; ...

5 days ago | 0

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Why I have the error Genetic algorithm script error no Global Optimization Toolbox ?
You have to license, download and install the Global Optimization Toolbox. There is no separate license for gamultobj. You m...

5 days ago | 0

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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...

6 days ago | 1

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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(...

6 days ago | 0

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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 ...

6 days ago | 0

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Finding length of time in between peaks.
I already addressed this in my Answer to your previous question on exactly the same topic. If you are having problems with it...

6 days ago | 0

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whats wrong with this code?
It works here. How are you calling your ‘aero_drag’ function? dens = rand v = rand A = randn(1,5) drag = aero_drag(de...

7 days ago | 1

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usage of ode45
imshow(imread('WhatsApp Image...16.45 PM.jpeg')) syms M(t) I_1(t) I_2 V(t) t g mu A Y T Eq1 = diff(M) == -g*V*A Eq2 = diff(...

7 days ago | 0

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find function not working with double inequality
The problem is in the ‘indf’ logic: indf = find(signal_freq-b<CenterFreqs<signal_freq+b); That performs the first comparision...

7 days ago | 1

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Identifying PTT of ECG and PPG signals
Without your data, it is going to be nearly impossible to suggest an approach to this. Also, without your data, it is impossibl...

7 days ago | 0

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Matlab fft plot axes
This would be my approach — Fs = 1000; Fn = Fs/2; L = 60; t = linspace(0, Fs*L, Fs*L+1).'/Fs; ...

7 days ago | 0

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Omit nans from data set when calculating weights
Since NaN values are considered to be ‘missing’, to remove them from a specific vector (or matrix), you can use the rmmissing fu...

7 days ago | 1

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Can anyone explain the difference in results for rainpl function between R2016b and R2021a?
The earliest available online information on rainpl is R2019a, so any changes between R2016b and R2019a are unavailable. (I don...

7 days ago | 0

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how to plot time and frequency domain by using FFT from CSV file?
Try this — A = readmatrix('FILE060.CSV'); Asz = size(A) t = A(:,1); s = A(:,2:end-1); figure plot(t, s) grid xlim([m...

8 days ago | 0

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Delete rows in a given array based on values in another array
Perhaps this — A = randi(99, 50, 1); Abfr = buffer(A,10) % Show Everything In 'A' B = randi(99, ...

8 days ago | 0

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