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Star Strider


Last seen: Today Active 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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Answered
Doubt in solving ODE45
It seems that ‘dis’ does not appear anywhere. L=20; v=20;%v (m/sec) T=L/v; tspan_1=[0:0.001:T];%time range y0_1=[0;0];...

etwa 5 Stunden ago | 0

Answered
How do you plot a line of constant value on a surface plot?
See if contour3 or contour3m will do what you want. [X,Y,Z] = peaks(30); figure surf(X,Y,Z) hold on contour3(X,Y,Z,[1 1...

etwa 6 Stunden ago | 0

Answered
How to properly create function for integration?
There are several problems with the posted code image. First, ‘z’ is not defined anywhere, and it is not an argument to ‘E_fu...

etwa 7 Stunden ago | 0

Answered
How can I plot the derivatives of the components of the solution to a system of ODEs?
The only way is to use al loop — tspan = [0 50]; z0=[0.01 0.01 0.01 0.01]; [t,z] = ode45(@(t,z) coupled(t,z), tspan, z0); ...

etwa 11 Stunden ago | 2

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Answered
Cannot calculate integral function
If you want a numeric result, use vpaintegral (introduced in R2016b) instead of int. Not all expressions have analytic integral...

etwa 12 Stunden ago | 0

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Answered
How to convert logarithmic to linear
If you have the Signal Processing Toolbox, use the db2mag function. If you do not have it: dB2mag = @(dB) 10.^(dB/20); ...

etwa 12 Stunden ago | 0

Answered
Matlab Polar Plot Legend does not match with the plot
I cannot run that and I amm not certain what you are are plotting. Create a handle for each polarplot call: th = linspace(0, ...

etwa 19 Stunden ago | 0

Answered
How to save output of double loop as a matrix?
Since ‘A’ is a matrix, save it as a cell array — for i=1:m for j=1:n A{i,j} = myfunction(...) end end .

ein Tag ago | 1

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Answered
Shaded Standard Deviation Corridors
There are NaN values in ‘x’, ‘y’, and ‘sd’. This ia frequent cause of patch failures. Remove them and it works! Try this ...

ein Tag ago | 1

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Answered
3D Sphere projection in Matlab
I worked on this for a while yesterday, without success. Today, I used a relatively straightforward approach that simply flips ...

ein Tag ago | 1

Answered
How would I go about writing this equation in matlabs?
There are several options, depending on what you want to do. syms x p(x) = 1/(2*sqrt(sym(pi)))*exp(-(x-5)^2/4) figure f...

2 Tage ago | 0

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Answered
How to save .mat file into hdf5 in matlab?
I have no recent experience with HDF5 files, however the h5write documentation for data indicates that it must be a numeric matr...

2 Tage ago | 0

Answered
Error with plotting my function
It works if you give ‘f’ a vector to work with — f = @(x) 2.^x-5*x+2; %Given Function xaxis = [0:0.5:2]; ...

2 Tage ago | 2

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Answered
I am trying to plot an ellipse using a polarplot function.
The polarplot function requires the angular measure to be in radians. Change that in the polarplot call and it works. (The e...

2 Tage ago | 0

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Answered
Am I using corrcoef correctly?
‘Am I using corrcoef correctly?’ Yes, except for squaring the result, and that will produce . H=log([0.01 0.02 0.03 0.04 ...

2 Tage ago | 0

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Answered
Converting a linear equation to decibel
The ‘theta’ vector likely needs to have more points, however that appears to be correct. I use a slightly different approach ...

2 Tage ago | 0

Answered
Sampling frequency and correct signal plotting
I believe this is simply an interaction of the sampling frequency and the signal frequency, typically referred to as ‘aliasing’....

2 Tage ago | 0

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Answered
Creating new table from another table
There are several ways to do this, including using the findgroups function. A relatively efficient way is just to do the comp...

3 Tage ago | 0

Answered
Amplitude detection in time series data
There are at least two functions you could experiment with, those being findchangepts and ischange. EDIT — (18 Sep 2021 at ...

3 Tage ago | 0

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Answered
How to calculate mantissa of 0.5
I created a little utility function to calculate the mantissa and exponent of a floating-point number a while ago, for my own us...

3 Tage ago | 0

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Answered
How to plot this exponential signal?
The error message is spot on! Use element-wise multiplication ... x=exp(-0.1*t)*sin(0.6*t); ↑ ← HERE so with...

3 Tage ago | 0

Answered
rearranging in a matrix
One approach — x = [1 1 0 0 ]; xr = reshape(buffer(x,nnz(x)).', 1, []); xr = xr(1:numel(x)) x = [1 1 1 1 0 0 0]; xr = ...

3 Tage ago | 0

Answered
How to calculate volume of surf plot (3d plot) en matlab?
The surf plot arguments are matrices, so use trapz: x = 1:10; y = 1:20; [X,Y] = meshgrid(x,y); z = exp(-((X-5)/5.*(Y-10)/10...

3 Tage ago | 0

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Answered
How to reduce data irregularly?
One approach would be to use the gradient function to calculate the derivative of the available data. This will be greater than...

3 Tage ago | 0

Answered
solving a system of ODEs in 3x3 matrix form
The easiest way would be to use the expm function. The expression changes slightly: A = rand(3); b = rand(3,1)...

3 Tage ago | 0

Answered
Smoothing a curve and conserving the first and the last value of the curve
Probably the only way to do that is to use the 'SamplePoints' name-value pair, and smooth all but the beginning and end points —...

3 Tage ago | 0

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Answered
10x10x15 matrix integration.
What are ‘X and Y axis’? I would use trapz and approach it as: AXY = A.*X.*Y.*A; Xint = trapz(AXY,1); ...

3 Tage ago | 0

Answered
How to plot two equal parts of axis y with unequal distances?
Set the tick locations (and displayed values if different) to specific values, and specify the tick format — x = zeros(1,5); ...

3 Tage ago | 0

Answered
not enough input arguments Urgent Help
The function declaration is: function [V] = Tank_Volume(R, h, L, H) and the function call is: V(i)=Tank_Volume(h(i),R,H); ...

4 Tage ago | 0

Answered
Help with global optimization problem
The Golbal Optimization Toolbox functions (as much as I like them) may not be appropriate for this. See if the rica function (t...

4 Tage ago | 0

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