# 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**

find the intersection of the four corner and trim the value out of the corner

Solve for the intersections, then plot to those limits — grid on syms stress1 stress2 shear12 SL_Ts=1800; SL_Cm=1400; ST_T...

3 hours ago | 0

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Integration of a function having constant parameter

Try this — syms a x F = int((4*a - 2*x + 4*a*x - 3*a*x^2 - 2*a*x^3 + a*x^4 - x^2 + x^3), x, 0, 1) Ffcn = matlabFunction(F) ...

4 hours ago | 1

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plot nonlinear equation in x y coordinate

Try something like this — syms x y SL_Ts=1800; SL_Cm=1400; ST_Ts=40; ST_Cm=230; SLT=100; k=((x^2/(SL_Ts^2))-((x*y)/...

4 hours ago | 0

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Interpolated contour plot with excel data

I’m guessing as to what ‘x’ and ‘y’ are, however it will be easy to reverse them if I guessed wrong. T1 = readtable('https...

4 hours ago | 0

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Plot scatter plot as shade

Try this — LD = load('conc.mat'); conc = LD.conc; t=[0;30;60;120;300;600;900]; figure plot(t, conc) hold on shadeWidth...

4 hours ago | 0

please give me answer what is wrong

The differential equaton apparently does not have an analytic solution. Integrating it numerically is an option — syms y(x)...

9 hours ago | 0

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ode89 and ode78 are unrecognized in MATLAB 2021a

From the last line in the ode78 and ode89 documentation — Introduced in R2021b .

12 hours ago | 1

Find a y axis increasing point in a plot -

Try something like this — x1 = -2:2; y1 = [0 0 1 0 0]; x2 = linspace(-2, 2); y2 = interp1(x1, y1, x2); [maxy2,idx2] ...

12 hours ago | 0

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Error: This statement is incomplete.

I strongly advise against using eval. Put all of the arrays into a cell array, and then address them appropirately — year...

14 hours ago | 1

Locating z-values at certain x-values

I am not certain what the desired result is, sp[ecifically finding the ‘z’ values that correspond to ‘x_sea’ or the reverse. ...

15 hours ago | 0

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Weibull distribution plot x-axes scale is wrong

Try something like this — %% Weibull [parmHat, parmCI]=wblfit(Cont_Wh_Wp); scale= parmHat(1); shape=parmHat(2); figure...

16 hours ago | 0

Find roots of a first order differential equation

Try this — r = 1; x = linspace(-2*pi, 2*pi, 25); y = Function(x,r); zxidx = find(diff(sign(y))); ...

17 hours ago | 0

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Problem with multi-layer antenna design using Antenna Designer

The ‘Index cannot exceed 0’ message indicates that there is nothing in the array being indexed (it is empty, indicating that it ...

24 hours ago | 0

this plot3 looks 2D on live script (pointing downwards as it should), and 3D (pointing sideways for no reason), why?

I cannot run that since the data are missing. However to see it in all its 3D glory, use the view function to rotate the came...

1 day ago | 0

Array Indexing and Function Handling question.

It would be necessary to define ‘F’ in terms of a single parameter vector — F = @(xy) [3*xy(1)+xy(2).^2 , xy(1).^2+3*xy(1)-1];...

1 day ago | 1

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How to put endpoint on Bar graph

In R2021b, this is straightforward (and described in Specify Labels at the Ends of Bars). y = [75.8 78.05; 81 80.30; 91 80...

1 day ago | 1

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how can I change my time so that it takes frequency 1/250 hz

If is the sampling interval, multiply it by the sampling instants to convert them to time — C = readtable('https://www.math...

1 day ago | 0

How to plot color ball use matlab?

This is an interesting problem! This should get you started — Facets = 40; numPatches = fix(Facets/5); [X,Y,Z] = sphere(F...

1 day ago | 1

split an audio file

Unless it is absolutely necessary to use reshape, use buffer instead. It is just easier. It only operates on one vector at a...

1 day ago | 1

matlab font 2021b

There is likely a way to set this programmatically, however the easiest way to change the fonts is to click on Preferences, then...

1 day ago | 0

How do I increase the x-axis to make my action potentials bigger

The X-limits need to be reduced in order to show the detail, and the last subplot needs to have its axes rescaled to show the de...

2 days ago | 0

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Symbolic ODEs aren't symbolic?

Because of the ‘R*s’ terms, the system is nonlinear. The vast majority of nonlinear differential equations do not have analytic...

2 days ago | 0

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How to calculate the duration of data points in days

Try something like this — Data = readmatrix('https://www.mathworks.com/matlabcentral/answers/uploaded_files/772213/pulses.txt'...

2 days ago | 0

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Error in ode45 (line 115) and odearguments (line 90)

There were two errors. First: dydt(2)=y(2)*(1-y(2))*((y(1)*(or*rr-br*re)-ar*rr); ↑ ← EXTRA UNMATCHE...

2 days ago | 0

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How to avoid using a loop here?

One approach — N = 5; tic [m,n] = ndgrid(1:N); A = 2*N + 1 - (m + n) toc Compare — tic A = zeros(N); for m = 1:N ...

3 days ago | 0

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Timeformat from HH:MM:SS to HHMMSS

Try this — time = datetime('12:30:00', 'InputFormat','HH:mm:SS', 'Format','HHmmSS') .

3 days ago | 0

Replace comma with dot after fopen

For MATLAB versions R2019a and later, the readmatrix function permits definition of the 'DecimalSeparator' (see the Text Files O...

3 days ago | 0

How to solve an ODE calculating the value of a variable inside a loop?

The problem is: x0 = X(end); so the error only occurs after the first iteration. The solution is: x0 = X(end,:) and thi...

3 days ago | 1

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how can I get the following graph from this data, changes are required in the code

Try something like this — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/771138/G2_A.txt', 'Va...

3 days ago | 0

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How do i fix line13; Parse error at'=': usage might be invaild Matlab syntax? why it gives error ?

If you are referring to Line 13, it appears that there is nothing to the left of the equal (=) sign. Perhaps the intention is...

3 days ago | 0