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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How to use integral when limits are anonymous functions
‘How do I overcome this?’ First, use the int function to integrate symbolic functions. It will return a numeric result if i...

ungefär 6 timmar ago | 0

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error in envelope function
If ‘x’ is a cell array (as I suspect it is, since a cell array would throw that sort of error), either change the addressing to:...

ungefär 7 timmar ago | 1

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Swapping X and Y Axis of a Figure for a One-layer Matrix
I can’t run your code. Try this — contourf(E.') instead. That will transpose the matrix. so it should display the way y...

ungefär 18 timmar ago | 1

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Generate a time series from power spectral density
In that event, just create a sine curve of the appropriate frequency or frequencies as determined by the PSD result. This will ...

ungefär 22 timmar ago | 0

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Trying to find the integral under the curve at a certain bandwidth
Try this — clear all close all clc L=10; n=1.45; c=2.9979e8; dt = 6e-12; T=10*2*L*n/c; t = (-T/2/dt:1:T/2/dt)*dt; N...

en dag ago | 0

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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'} ...

en dag ago | 0

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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...

en dag ago | 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 ...

2 dagar ago | 1

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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...

2 dagar ago | 0

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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...

3 dagar ago | 0

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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 ...

4 dagar ago | 0

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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 ...

4 dagar ago | 0

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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...

5 dagar ago | 0

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

5 dagar ago | 0

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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...

6 dagar ago | 0

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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)...

7 dagar 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...

7 dagar ago | 0

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Answered
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...

8 dagar 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...

8 dagar 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 ...

8 dagar ago | 0

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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...

8 dagar 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...

9 dagar 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...

9 dagar 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...

9 dagar 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...

10 dagar 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...

10 dagar 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 ...

10 dagar 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...

10 dagar 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...

10 dagar 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} = ...

12 dagar ago | 0

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