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# Star Strider

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14 675 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

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How do I fix my legend?
For every plot call, return a handle: h1 = plot(a1,b1,'ko','LineWidth',3); . . . h2 = plot(c1,d1,'bo','LineWidth'...

ungefär 3 timmar ago | 0

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Extract hourly data from minute data over a year
Try this: T1 = readtable('weather_data_2019.txt'); Idx = minute(T1.Datetime) == 0; OutTable = T1(Idx,:) producing (for this...

ungefär 6 timmar ago | 1

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How can you make an input to a symbolic variable?
Try this: varprompt='Enter Variable (space-separated):'; var=inputdlg(varprompt) v = regexp(var, ',', 'split') syms(v{:}) ...

ungefär 7 timmar ago | 0

How to plot both real and imaginary part of complex exponential?
See my Answer to your duplicate Question: How to plot both real and imaginary part of complex exponential?

ungefär 7 timmar ago | 0

Numerical integration in MATLAB
Try this: c = @(T) (h.^2 .* D) ./ (2 .* pi * pi * vs * kb .* T .* T); fun = @(x,T) ((x.^4 .* exp((h.*x) ./ (kb .* T))) ./ (((...

ungefär 9 timmar ago | 0

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Interpolate NaN on graph
If the data have NaN as the value of the dependent variable, and the independent variable is continuous (with no NaN values), th...

ungefär 9 timmar ago | 0

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Finding all the zeroes of a discontinuous function in a particular range
It may be version-dependent. In R2020b (Update 1), I get: extrema = 13.3333 -1.0 ans = -26.666666666666666666666...

ungefär 10 timmar ago | 0

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EMG bandpass filter to remove 50 Hz power line
With a sampling frequency of 10 Hz, the highest frequency that can be uniquely represented is 5 Hz, which is much too low for an...

ungefär 10 timmar ago | 0

error in my code
The way you coded ‘R’: R=1000*[5, 100, 200, 250]; it only has 4 elements. Nothing exists beyond ‘R(4)’.

ungefär 12 timmar ago | 1

Finding Best Fit for Log Scaled Graphs
It is best to fit the power function using a nonlinear approach: x = [0, 0.00027036151034654, 0.00115093883458806, 0.002234322...

ungefär 12 timmar ago | 0

How to plot both real and imaginary part of complex exponential?
For best results, replace ‘j’ with ‘1j’, then convert the result to double to use plot (since fplot is likely to be more difficu...

ungefär 14 timmar ago | 1

Changing the legend color
Try something like this: y = linspace(0,50,50); % Create Data v = 1:14; ...

en dag ago | 0

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plotting concentric circles using contour
Use the axis function, specifically either: axis('equal') % Function Expression or: axis equal ...

en dag ago | 0

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Graph help in matlab
This is not your function, however it illustrates the ‘logical indexing’ approach to such problems: f = @(x) (2-2*x).*(x <= 0)...

en dag ago | 0

Pseudo Element by Element Vector Subtraction
See if this does what you want: C1 = A(:,1).' - B(:,1); % Col #1 In ‘A’ - Col #1 I...

en dag ago | 0

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Numbers in command window printed 10000 times smaller
I suspect there is an exponent indication out-of-view in the image you posted. When I read and reshape your file as in your p...

en dag ago | 0

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How to write Pearcey functions?
I would code them as: Pe1 = @(x) integral(@(s) exp(1i*(s.^4 + s.^2.*x)), -Inf, Inf, 'ArrayValued',1); Pe2 = @(x,y) integral(@...

en dag ago | 0

Is there any ways to find all elements' rows and cols number at once?
Meet the size function!

en dag ago | 0

Separate a time signal for each frequency
The pspectrum function (introduced in R2017b) with the 'spectrogram' type may be what you want. It produces a spectrogram plot ...

en dag ago | 0

Error when using fminsearch to find least squares fit of data using a given equation
I can’t figure out from your code what your independent and dependent variables are. As a general rule, the argument to fmins...

en dag ago | 0

How do I convert a transfer function of a low pass filter to bandpass?
If you want to use the Signal Processing Toolbox functions, this works: syms s; N=4; for k=1:N w=((2*k+N-1)/(2*N))*pi; ...

2 dagar ago | 0

Designing a bandpass filter
See if the bandpass fucntion works for you.

2 dagar ago | 0

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How to select every second number from a file of numbers separated by a comma
I looked at ‘UE1.txt’ and I initially could not make any sense out of it. It’s apparently supposed to be a multi-channel record...

2 dagar ago | 0

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plotting a graph with different conditions using if statement
Your code can be made significantly more efficient by using vectorisation and ‘logical indesing’: mu_a1 = 0.1; %absorption coe...

2 dagar ago | 1

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Deleting Some initials of The Matrix
It depends on the functions you have available. It appears to be a text file, so one option would be textscan: fidi = fopen('...

3 dagar ago | 0

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Requesting help for piecewise ploting
The Symbolic Math Toolbox and here particularly the piecewise funciton may not be the best option for this problem. Use ordin...

3 dagar ago | 0

Need Help New to MATLAB
To make them not be fractions, use vpasolve or vpa on the result: F2s = vpasolve(Fwy+F1y+F2y == 0,F2) F1s = vpasolve(Fwx+F1x+...

3 dagar ago | 0

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Matlab returns empty symbol when solving laplace transform
Try this: syms s t C1 C2 R1 R2 i(t) I(s) eqn(t) = 0 == R1*i(t) + R2*i(t) + diff(i(t), t)/10 + int(i(t), t)/C1 + int(i(t), t)/...

3 dagar ago | 0