# Star Strider

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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**Content Feed**

How to convert day information to a number?

Experiment with something like this — daynr = @(x) find(strcmp(x, {'Mon','Tue','Wed','Thu','Fri','Sat','sun'})); nr = day...

etwa 12 Stunden ago | 0

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Reading data of nonstandard format

I use textscan for these problems. Try this — fidi = fopen('reconstructed[1].txt','rt') k1 = 1; while ~feof(fidi) HL...

etwa 17 Stunden ago | 0

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How to draw a line between two points on a graph?

I recognise that code! I added this plot call to the others in the loop: plot([minx maxx], [0 0], '-k', 'LineWidth',1) ...

etwa 18 Stunden ago | 0

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Restore old editor in R2021b?

Set the fonts by clicking on Preferences in the ENVIRONMENT section of the MATLAB toolbar (at the top of the window in the HOME ...

etwa 19 Stunden ago | 0

Help Plotting Diffusion Equation in MatLab

One option is to stack them in the same axes — x = linspace(-200, 200); v = logspace(-2, 2, 10); y = exp(-(x./v(:)).^2); ...

ein Tag ago | 0

Impossible to do an indexing

I suspect the problem is with: soleus(stim_Hz) Here, ‘stim_Hz’ must be either logical, or integers greater than 0. There are...

ein Tag ago | 0

Converting syms to double

I have no idea what you are actually doing, however converting between symbolic and double is straightforward (if inefficient in...

ein Tag ago | 0

how to assign indexes to a function handle?

‘But I want to use a vector "f" insted of a single number to have a vector of "TL" values.’ I cannot run that because there a...

ein Tag ago | 1

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smoothdata function not working for matrix . any one have ideas to what is going on?

Try this — LD = load('mat.mat'); a = LD.a; for k = 1:size(a,2) a_smoothed(:,k) = smoothdata(a(:,k)); end x = 1:si...

2 Tage ago | 0

problem with fit function for data

The fit function requires column vector arguments. Force that sith the ‘(:)’ subscript noitation. E = [416.861, 818.7, 109...

2 Tage ago | 1

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How to use one marker for looped plots in legend

I cannot run the posted code, however the solution may be straightforward. figure hold on for k = 1:50 hs{1} = scatter...

2 Tage ago | 0

fit 2nd order differential equation parameters to data

The problem appears to be not allowing the intial conditions to be estimated as parameters as well as the initial value of ‘a_m’...

2 Tage ago | 0

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Using solve to find intersection points

It’s as simple as it looks — syms x f(x) = exp(-x^2) g(x) = sym(0.8) xi = solve(f == g) xi_vpa = vpa(xi) .

3 Tage ago | 0

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How can I simplify the folllowing equation

One approach — syms x Eqn = 2*x^2 - 2*x*(2*x^2 - 1) + 2*x*(2*x*(2*x^2 - 1) - 2*x^2 + 1) - 1 Eqn = simplify(Eqn, 500) .

3 Tage ago | 0

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How to plot data with two different X- axis in a single plot?

One option is to use the subplot function in a loop — Z = readtable('https://www.mathworks.com/matlabcentral/answers/uploade...

4 Tage ago | 0

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translating and solving an equation with values of x and y known

In the third term, the square root is of the numerator only, not the entire expression, amd the denominator does not appear to h...

4 Tage ago | 0

To determine whether the system is stable.

Welcome to the wonderful world of floating-point approximation error! See ‘Check’ and ‘Check_max’ for an illustration of the ...

4 Tage ago | 1

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How to properly format a data table with fprintf?

In the numeric edit descriptors, the value to the left of the decimal is the field width (this includes all the numbers, the sig...

4 Tage ago | 0

Find which matrix row contains average minimum value

One approach — M = rand(288,365); AMV = mean(min(M)) % Average Minimum Value [val,idx] ...

4 Tage ago | 0

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trying to find theta

The Question lacks clarity. % plot mountain Mn_x = [0, 1000, 3014.8]; Mn_y = [0, 0, 616]; plot (Mn_x, Mn_y) hol...

4 Tage ago | 0

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Solve for x given y and plot

Depending on what you wan, either use fzero or interp1 — y = @(x) (2 * exp((2*x)/3)) - ((7*x.*exp((2*x)/3))/3); x = linspace(...

4 Tage ago | 0

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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];...

5 Tage ago | 0

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...

5 Tage ago | 0

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...

5 Tage ago | 0

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); ...

5 Tage ago | 2

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Cannot calculate integral function

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

5 Tage ago | 0

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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); ...

5 Tage ago | 0

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, ...

5 Tage ago | 0

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 .

6 Tage ago | 1

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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 ...

6 Tage ago | 1

| accepted