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I don't know why this code doesn't stops :(
res(3) == 0 and res(4) == 0 are two nonlinear equations in the unknowns yp(3) and yp(4). ode15i seems to have problems following...

2 years ago | 0

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Delay differential equations where every variable can take on multiple delays
I don't understand your mathematical formulation. Should the summation be over j instead of i ? And shouldn't there be a bracket...

2 years ago | 0

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Solving Multi-variable Partial Differential Equation
The only thing you can get with the "boundary condition" you gave is the solution on the characteristic curve of the PDE through...

2 years ago | 1

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Curve fitting with more than 3 variables
Do you really think that there is a causal correlation between the housenumber and the energy from the grid ? So if the house nu...

2 years ago | 1

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i have some error in my MATLAB code .
B*delta_e(t) is undefined since B and delta_e(t) are both 4x1. Maybe you mean B.*delta_e(t) instead.

2 years ago | 0

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How to draw ellipse around my data
https://uk.mathworks.com/help/stats/fitgmdist.html After fitting, you can plot a 90% ellipse around your data. What does it me...

2 years ago | 0

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Event function with DAE system
options = odeset('Mass', M, 'MassSingular', 'yes', 'RelTol', 1e-4, 'AbsTol', 1e-6,'Events',@event); function [position,isterm...

2 years ago | 1

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Answered
I get error in unrecognized function or variable 'T'.
I changed the bold parts below: T = t; for j = 1:length(t) %with drugs T(j+1)=T(j)+dt; M13(j+1) = M13(j)+...

2 years ago | 0

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Answered
Error in ode15s: incompatible sizes arrays, while no errors in function
if Re(i,j)/Re_check(i,j)<0.95 || Re(i,j)/Re_check(i,j)>1.05 fprintf('Re difference too big \n') return end if Re(i...

2 years ago | 0

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Answered
How to draw 3d plot with system of equations
Use https://uk.mathworks.com/matlabcentral/fileexchange/9261-plot-2d-3d-region %plotregion([1,2;2,1;1 -1;1 -4;-4,1],[-1;4;-1;-...

2 years ago | 0

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Answered
interpolation of coordinates in space using interp3
Given two points P1 = [1 3 4]; and P2 = [3 6 -1]; you can connect them by a line s = @(t) (1-t)*P1 + t*P2; and choose poi...

2 years ago | 0

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How can I plot an ellipsoid using the ellipsoid function with a given equation in the form of ax^2+by^2+cz^2 = 1.
f = @(x,y,z) x.^2 + y.^2 + z.^2 - 1; fimplicit3(f)

2 years ago | 0

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incorrect dimensions in data set
The code works technically. But after all the changes I made, it's not clear if it does what you want. This line needs correcti...

2 years ago | 0

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Index in position 1 is invalid. Array indices must be positive integers or logical values. "Ideas of fractal fractional using exponential kernel"
sum(((u(i+1-k,j)-u(i-k,j))/deleta) and k = 1:j For i <= j, the first index in the matrix u becomes <=0.

2 years ago | 0

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Unable to perform assignment because the size of the left side is 5-by-75 and the size of the right side is 5-by-87.
Problem1() function Problem1 %% Parameters values delta1=0.1; Ha=0.1; d1=0.1; d2=0.1; beta=0.1; Pr=1; alpha= pi/4; S1=0.1; ...

2 years ago | 1

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Create an array with only the increasing values of a pressure time series.
I prefer a clean for-loop: a_monotone(1) = a(1); for i = 2:numel(a) if a(i) > a_monotone(end) a_monotone(end+1) = a(i)...

2 years ago | 1

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calculate the normal for a plane passing through more than three points
If the points in V1_in.mat all lie in a common plane, you can arbitrarily pick three points and define these points as P. If th...

2 years ago | 1

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Plotting of colormap for single value in x axis and multiple values in y axis
Use a contour plot https://uk.mathworks.com/help/matlab/ref/contourf.html with time and thickness as axes and temperature for ...

2 years ago | 0

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I want to solve this system of differential equations. Is there any code that can solve this?
Note that there is a discrepancy between your code and your graphics for the second ode. I took the version from the graphics ( ...

2 years ago | 0

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¿Qué significa la matriz que devuelve la función chol(A), si A es definida positiva pero no es simétrica?
From the documentation: If A is nonsymmetric, then chol treats the matrix as symmetric and uses only the diagonal and up...

2 years ago | 0

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Solving First order ODEs simultaneously
I'm quite sure there is no analytical solution for your system of ODEs since the right-hand sides are nonlinear in the unknown f...

2 years ago | 1

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How to make change in the algorithm to start and end at a same point?
Is this an attempt to code the Travelling Salesman Problem ? If yes: it doesn't matter where the tour starts and ends since it ...

2 years ago | 1

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Why I am getting "Matrix is singular to working precision"?
syms w x y z c1 lambda % system of linear equations eqn1 = 2*w + 3*x + y -11*z == 1; eqn2 = 5*w - 2*x + 5*y - 4*z == 5;...

2 years ago | 0

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Trying to solve 2 dimensional Partial differential equation using Finite Difference Method
For those who might be interested in a finite volume code for the equation above. Skerdi Hymeraj asked for such code, but delet...

2 years ago | 0

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Finding Imaginary roots of a function
As you can see from your code above, you choose tauinit = [0 0] for k = 501, and your function returns NaN for the real part of ...

2 years ago | 0

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How do I calculate the area of the graph area below the baseline? (matrix plot)
Your X-vector has two elements more than your Y-vector. After you have corrected this, you could use idx = find(Y<=214.5); val...

2 years ago | 1

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Matlab creates same input values every time? Why?
Shouldn't the Matlab give me different values every time I open and close it? No. But you get different values if you call the ...

2 years ago | 0

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How can I convert a 666by3 matrix into 666 row matrices?
If M is your 666x3 matrix, then Mi = M(i,:) is the i-th row of M and is of size 1x3. You don't need the conversion to 666 1x3 ve...

2 years ago | 0

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Which boundary condition is correct or what will be the correct alternative?
If you can estimate the heat transfer coefficient k between PVC material and roller, you could use -lambda_PVC * dT_PVC/dn = k ...

2 years ago | 0

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Answered
How can I plot graph only specific coordinate values from a PDE solved using the FEM method?
For a stationary computation: https://uk.mathworks.com/help/pde/ug/pde.stationaryresults.interpolatesolution.html What is the ...

2 years ago | 0