Star Strider

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14,861 total contributions since 2012

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

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Answered
tf2ss not returning the correct State Space form
The result is correct. The exact configuration doesn’t matter, so long as all the matrices and vectors work together (and produ...

2 hours ago | 0

Answered
How do I generate a polynomial from roots that are repeated?
Iinteresting. I would expect no repeats, and complex conjugate values instead. Try this: rts = [ -0.7437 - 1.4178i ...

3 hours ago | 0

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Answered
add standard deviation value and text on bars
When I try to run your code, I get: Unrecognized function or variable 'X'. In its absence, try this: Y=[0.9 0.83 0.700;1.58...

6 hours ago | 0

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ODE symbolic result plotting with fplot()
I am not certain what the problem is with the original function. If you simplify it first: phi = vpa(simplify(phi, 'Steps',...

6 hours ago | 0

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solve 3 order differential equations
Without seeing your ODE solver call, I cannot determine what the problem is. This runs without error for me (in R2020b): ...

6 hours ago | 0

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How can I mark wheezes on a plot?
Try something like this: wheezes = sort(randi(100, 10, 1)); % Create Data ws...

1 day ago | 0

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Fprintf modification in matlab
Those are all preferences. See the Fonts section. There is no other way (to my knowledge) to change them. Also, I poste...

1 day ago | 0

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Need help.... How to plot sequences
The mod function and the colon,: operator are your friends!

1 day ago | 0

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sampling time causes scaling of simulation results.
It may be appropriate to specify the the sampling time in the ss call. See Create Discrete-Time State-Space Model. Another p...

1 day ago | 0

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How can we do for following fprintf formating
Try this: fprintf('\tx%c\n', char(178)) producinig: x² .

1 day ago | 0

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Answered
How to Solve an Equation with Integral and Gamma functions?
I cannot achieve the result you describe. The code I used to (unsuccessfully) solve for it is: F = @(S) abs(S) - 0.01 * gam...

2 days ago | 0

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How to plot point clouds and linear regression line in the same plot?
Use the hold function.

2 days ago | 0

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How to Solve an Equation with an Integral for the Integral Range Parameter?
The gammainc function does not take complex arguments, so this is likely the best you can hope for: F = @(S) S - 0.01 * gammai...

2 days ago | 0

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Answered
ODE45 to solve a 2nd order differential equation with a parameter that changes in time
Interp[olate to find the appropriate values of ‘heave’ (that I call ‘heavet’ in ‘pitchODE’ ‘dxdt2’): function [dxdt] = pitchOD...

2 days ago | 1

Answered
Percentiles without Statistics Toolbox
Try this: x = 3*randn(1,100)+5; % Create Data figure yyaxis left h = hi...

2 days ago | 0

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Answered
error with function bode
Rename your ‘conv.m’ file to something else, perhaps to ‘myconv.m’ or to something else that makes sense in the context of its u...

2 days ago | 0

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Sorting time in 1 hour time slots.
One approach: A = datetime([zeros(100,4) randi(1440, 100, 1) zeros(100,1)]); % Create Data [H,~,ix] = unique(hour(A)...

3 days ago | 0

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why is my plot plotting blank?
The value of ‘Cd’ is 0 in the code you posted, so ‘y’ is uniformly -Inf.

3 days ago | 0

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How to get spatial frequency from FFT?
The Fourier transform neither knows nor cares whether the units of the independent variable are time, space, or anything else. ...

3 days ago | 0

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Answered
How to plot particle trajectories and normalise to 0,0 origin?
This will normalise everycell to begin at (0,0): testdata = readmatrix('Amadeus Xu testdata.xlsx'); [Uid,~,ix] = unique(testd...

3 days ago | 1

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Answered
How can I mix two signals in MATLAB?
Ther esult would appear to be a single-sideband suppresed-carrier signal (with only the upper sideband). See if the demod funct...

4 days ago | 0

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How can I import from Excel CSV
Use readtable to read it: T1 = readtable('sample.csv', 'VariableNamingRule','preserve', 'HeaderLines',22); The 'Headerlines' ...

4 days ago | 0

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Smoothening the data of Iv loop
That looks like a hysteresis loop. See if the approach in how to find ascending and descending of hysteresis loop? will fit it ...

4 days ago | 0

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Answered
Fitting data with multiple inputs, ODE equation, and lsqnonlin
The fundamental problem is that lsqnonlin ~= lsqcurvefit! They are definitely not interchangable, and have different argument l...

4 days ago | 1

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Answered
Matlab not recognizing dates
You did not mention how you were importing them. Try importing them this way: dv = {'202011' '202012'} datetime(d...

5 days ago | 0

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Answered
How to generate one square pulse?
Try this: sqpuls = @(t,t1,t2) (t>= t1) & (t <= t2); t = linspace(-1, 1); figure plot(t, sqpuls(t, -0.5, 0.5), '-r') gr...

5 days ago | 0

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How can I change the format of the answer?
I am not certain what you want. Try the vpa funciton: dphi = vpa(dphi, 5) producing: dphi = (1.25e-7*s^2 + 2.0438e-13)/...

5 days ago | 0

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Answered
Only getting zero as my output for ode45
Give it something other than 0 as the intial condition, for example: X0 = 0+eps; That worked when I tried it.

5 days ago | 0

Answered
How to choose population and generations for GA?
I use an optimoptions structure for this. Example — PopSz = 500; Parms = 3; opts = optimoptions('ga', 'PopulationSize',Po...

5 days ago | 0

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Answered
Array inputs in lsim function
Likely the easiest way is to create an (Nx3) matrix for ‘u’, with the constant inputs as constant vectors: N = 3501; u = [one...

5 days ago | 0