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Star Strider

9,762 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

NOTE: I do not respond to emails or personal messages, unless they are about my File Exchange contributions.

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How can I work out the median of frequency tables?
I would use the frequency vector *|‘B’|*, since it has the information you need. Try this: A = sort(rand(1, 35)); ...

2 hours ago | 0

Minimizing a multivariable function
Your code works for me as you posted it. (I added an *|end|* as the last line of the function, because I have a test function I...

2 hours ago | 0

how i plot 2 equations at different period in one graph?
Try this: x = @(t) (sqrt(2)*1.414*exp(-t).*sin(t+0.785)).*((0 < t) & (t < pi)) + (sqrt(2)*exp(-t).*sin(t+0.785)-exp(-t+pi)...

15 hours ago | 0

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Using fminsearch to find least distance between 12 points
I can’t run your code since I don’t have your constants. Try this instead: x0=rand(2,1); Using *|0|* as an initial...

17 hours ago | 0

Plotting two linear equations
Use ‘logical indexing’: x = linspace(-5,2); f = @(x) (-1).*(x < -1) + (x.^2 + x).*((x >= -1) & (x < 2)); figure(...

18 hours ago | 0

How to eliminate Nan
One option: x=[0.162071097716028 0 0.276531475376737 0 0.264268578570244 0.247172330667782 0.0276055958119857 0.0223509218...

19 hours ago | 0

How to take RMS of every 10 values in a matrix and output this?
Try this: A = randi(9, 66000, 4); % Create Matrix Ar = reshape(A, [], 4, 10); ...

20 hours ago | 0

Hey guys. I am trying to solve the equation of motion for a 2D 2-point-vortex. Im not sure if i am doing it right and how to plot the answer system. Can anybody look at my script and give some advise? Im quite new to matlab
Your concept is correct. However you are not calculating the derivatives correctly. You have to step through your *|‘PtV’|* fu...

20 hours ago | 0

Hello! Tell me please, on the basis of what literature is the model made "Muscle Reflex Parameter Estimation" https://www.mathworks.com/help/sldo/examples/muscle-reflex-parameter-estimation.html?s_tid=srchtitle.
MathWorks usually cites the references it uses. This is a simple spring-mass-damper system that MathWorks may have developed it...

1 day ago | 0

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How to solve these differential equations?
You can set the equations up easily enough using the Symbolic Math Toolbox: syms C(r) T(r) beta gamma phi Y dC = diff(...

1 day ago | 0

How to display Intersection of two graphs
You need to create *|‘T_A’|* and *|‘T_R’|* as _anonymous functions_. After that, you can use *|fzero|* to calculate the interse...

1 day ago | 1

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Effects of parameter on oscillatory behaviour.
Leave *|‘Kc’|* as a symbolic variable. Then you can vary it in your *|fsurf|* call: A=2; %Cross Sectional Area of the Tan...

1 day ago | 0

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How can I write a program that indicates a number if it is integer or not?
Use the <https://www.mathworks.com/help/matlab/ref/rem.html *|rem|*> (link) or *|mod|* (linked to in that page) functions. ...

2 days ago | 0

My fitness function for timetabling in ga
You need to subscript the *|‘x’|* variables, since they are elements of a vector. You can also create *|‘my_fun’|* as an an...

2 days ago | 0

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Curve fitting with 3 variables
There are several ways, depending on what you want to do. I would begin with the Statistics and Machine Learning Toolbox <https...

2 days ago | 0

How to search a word both uppercase and lowercase given a specified string?
The <https://www.mathworks.com/help/matlab/ref/regexpi.html *|regexpi|*> (link) function is the _case-insensitive_ version of *|...

2 days ago | 0

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How to continue the matrix pattern
I can barely read your code and I can’t run the image you posted. That aside, the <https://www.mathworks.com/help/matlab/re...

2 days ago | 0

How to solve equations with data stored in a cell arrays
I would simply do this: syms a Ind = 13; Rs = 5; Ind = 0:3:15; for i = 1:numel(Ind) Sol{i} = solve((a/...

3 days ago | 0

How to set all elements of a matrix that meet a certain criteria to NaN?
Try this: A(A > 1E+20) = NaN;

3 days ago | 0

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Fitting equation to data points
Try this: fy = @(L,Vr,x) (L./Vr)-((L./4.316).*cosd(x)); x = [22.96, 88.2, 114.275, 85.3]; y = [0.1422, 0.157967,...

3 days ago | 1

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How to plot solid concentric circles in a meshgrid?
Try this: theta = linspace(0, 2*pi, 100); [X, Y] = meshgrid(1:1:4, theta); a = 0; b = 0; figure(2) plot...

3 days ago | 1

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Help with 3D-plotting?
Tweak *|figure(2)|* by adding a *|patch|* call: figure(2) u1 = double(u_1) u2 = double(u_2) syms r v colorma...

3 days ago | 0

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How to quickly find the position of a value in a sorted column data?
Try this: V = linspace(-80, 45, 150); % Create Vector B = -78; idx = find(V <= B, 1, 'la...

3 days ago | 0

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how to mirror plot in x=4 axis
We do not give complete solutions to homework problems here. I present an approach to an analogous problem to give you a _h...

4 days ago | 1

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How to plot line on surface object
*_‘Any suggestion?’_* Experiment with *|plot3|* instead of *|plot|* to plot a line on a *|3D|* plot. *_Example_ —* ...

4 days ago | 0

replace only nonzeroes with per-column text and value
Try this: data = [11,111; 0,222; 33,0; 0,0; 55,555]; strvct = sprintf('foo:%d\tbar:%d\n', data'); result = regexprep...

4 days ago | 0

How can I use symbolic variables
Try this: rp = sym('rp',[1 10]); for n=1:10 a(n)=sqrt(n*3-1/n); c(n)=a(n)/rp(n); end

4 days ago | 1

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How do I solve the transcendental equation to form a vector with the results?
This seems to be homework. You first need to create a function from your equation that you can solve for *|‘x’|* that is also a...

5 days ago | 0