Star Strider

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15.749 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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Answered
Plot 3D Graph and make level curves
Use the plot3 function. If you then want it as a 2D plot, use the view function to rotate it.

ongeveer 2 uur ago | 0

Answered
How to integrate dataset over a certain domain ?
Perhaps: load data.txt S_v = data(:,2); T = data (:,1); Trange = (T >= 0.1) & (T <= 2.5); I_H = trapz(T(Trange), S_v(Trang...

ongeveer 6 uur ago | 0

Answered
3D plot from excel data
Try this: T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/593500/prova_stress.xlsx', 'VariableN...

ongeveer 6 uur ago | 2

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Answered
Find all the grid points that are inside of the circle
Use the inpolygon function.

ongeveer 8 uur ago | 0

Answered
Draw Signal graph from a frequency domain representation
That is not possible with only the information shown in the plot image. Inverting the Fourier transform of the signal require...

ongeveer 9 uur ago | 0

Answered
Step matrix where each value is repeated
Use the repelem function (introduced in R2015a).

ongeveer 11 uur ago | 0

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Answered
How to solve a linear system A * X = B when B and X are matrices instead as vectors?
The lsqr function is primarily used for sparse systems. There are a number of other options for iterative solutions summarised ...

ongeveer 12 uur ago | 0

Answered
Curve fitting of growing measurement data set
This is called ‘sequential parameter estimation’. A very good description of it is Sequential Methods in Parameter Estimation b...

ongeveer 12 uur ago | 0

Answered
I can't load csv files properly.
Since .csv files are strictly numeric (although they can haved the first row as non-numeric headers), the files could have nonum...

ongeveer 15 uur ago | 0

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Answered
How can I find the Q and S waves for this Particular ECG Data Set?
Assuming your EKG is Standard Lead II (we have no idea), the islocalmin function would likely work, however neither the Q or S d...

1 dag ago | 0

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Answered
FFT of discrete signal .Should use nextpow2 or not
Using nextpow2 is not necessary. It will make the fft calculation a bit more efficient, and it will increase the frequency reso...

1 dag ago | 0

Answered
How can I add a print the first bar with a color, second with color different and the last with a different color in subplot ?
The only way that I am aware of to plot the individual bar colours is to use a loop: x1 = [1;2;3] y1 = [91,25,3]; cm = [1 ...

1 dag ago | 0

Answered
How to plot the point where two complicated graphs cross?
Clever animation! Since I assume you wnat to know where the ‘x_eartoMars’ and ‘x_mars’ intersect, the easiest way is to simpl...

2 dagen ago | 0

Answered
Remove text in a string with numbers
Try this: A = {'Model1__DK1_5450.0' 'Model2__DK2_6969.0' 'Model3__DK3_3398.0' 'Model4__DK4_-777.0'}; Ou...

2 dagen ago | 0

Answered
Ordinary Differential Equations (ODEs)
Change the ezplot call to fplot: syms t y(t) ysol=dsolve(' D2y + Dy + 4.25*y = 0','y(0)=2','Dy(0)=1'); y(t)=simplify(ysol) ...

2 dagen ago | 1

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Answered
Error using round every time can anyone please help me with this?
Convert ‘height’ to double first: stage = round(double(height),4) %%%LINE 18%% .

2 dagen ago | 0

Answered
Adding Error Bars to a grouped Bar Plot
Change the errorbar call slightly to: errorbar(ctr, ydt, WerrL, WerrH, '.', 'MarkerSize',0.25) That should do what you want. ...

2 dagen ago | 0

Answered
Displaying arrays alongside fprintf() text.
Try this: A = zeros(5); TA = array2table(A, 'VariableNames',num2cell('A':char('A'+size(A,2)-1)), 'RowNames',num2cell('A':char...

3 dagen ago | 0

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Answered
How to fitt a power function to data
This uses only basic MATLAB functions. No Toolboxes are required. x = 1:100; ...

3 dagen ago | 0

Answered
Try to solve System of Linear Equations
One option: syms x y eqn1 = x+y == 250; eqn2= 10*x+45*y ==24000; eqn3 = x+3*y ==3360; eqn4 = 10*x+15*y ==1440; eqns = [e...

3 dagen ago | 0

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Answered
Input argument "x" is undefined.
Instead of using the single quotes, call the function in ode45 with a function handle as: [t,x]=ode45(@ckt,tspan,x0); so the ...

3 dagen ago | 0

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Answered
Matlab graph not showing
Use element-wise division (./) instead of (/) and it works — s1=0.535*exp(1i*2*pi/3); s2=0.535*exp(1i*pi); s3=0.535*exp(1i*4*p...

3 dagen ago | 0

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Answered
Step response with initial condition
To set the step amplitude to 10, try this: k=0.2; t2=400; s = tf('s'); u_del=(0.0022*k*(s+0.06931)*(s^2+0.4852*s+0.1492))/(...

4 dagen ago | 0

Answered
Plotting date (number) on x-axis
It is necessary to be creative with the plot and the tick labels. Try this: DL = load('april.mat'); ex1 = DL.ex1; Q1 = ex...

4 dagen ago | 0

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Answered
Error in using syms
Remove the single quotes, define ‘x’ as ‘x(t)’, and define ‘Dx’ (and ‘D2x’ if you want to), explicity: syms x(t) t s X F Dx ...

4 dagen ago | 1

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Answered
using the vertical bars in calculation
I am not sure what you are asking. Perhaps the abs function?

5 dagen ago | 0

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Answered
How can I plot sequential data of a matrix
Try this: A = [0 329.62 0.01 329.61 0.014 329.60 0.2 329.59 0.00 329.63 0.05 329....

5 dagen ago | 1

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Answered
How can we fill a region defined by a implicit function?
I am not certain what you want. Try this: f=@(x,y) sin(x).*sin(y)-0.5; figure fp1=fimplicit(f,[-10,10,-10,10]); hold o...

5 dagen ago | 0

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Answered
Keep y value below certain value in a loop
Try something like this: x = linspace(0, 5*pi, 250); Capacity = 0.7; limit_y = @(y,Capacity) (y<0).*0 + (y>Capacity).*Capaci...

5 dagen ago | 0

Answered
Error converting from sym to double: Unable to convert expression into double array
Try this to create ‘T’ as a vector: n = 5 % Define ‘n’ syms T T = sym('T', [1 n]) produc...

5 dagen ago | 0

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