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I'm trying to solve a 2nd order ode with ode45, but have no idea where to start.
After dividing your equation by t, you can just follow the example Solve Nonstiff Equation under https://uk.mathworks.com/hel...

1 year ago | 0

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How to solve for 1D non homogenous ODE by Finite element method
I usually set A(1,1) = 1, F(1) = 0, A(N+1,N+1) = 1, F(N+1) = 2 and only loop from 2 to N here: %%%% Assembling %%%% for i=1:...

1 year ago | 0

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How do I change my scalars to fit my normpdf?
xq = 0:100; mu = [25, 50].'; sigma = [5, 10].'; ndist = 1./(sigma*sqrt(2*pi)).*exp(-((xq-mu)./sigma).^2); plot(xq,ndist) g...

1 year ago | 1

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Answered
newton raphson for nonlinear heat equation scheme
Why don't you use "pdepe" ? Ten lines of code maximum, and you are done. To get rid of the error in the above code, replace % ...

1 year ago | 0

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How to quantify shape similarity between two vectors.
Shift the curves by their means first so that the means of all objects lie in the origin (0). This will remove translational dif...

1 year ago | 0

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input appears to be a function and variable and exceeds the number of array elements???
You define a string of length 59 named "input". Then you want to use "input" as the MATLAB command to request user input for "ag...

1 year ago | 0

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How to solve for the maximum or minimum value of a symbolic function
syms Vr theta_r Vse rho gamma positive real syms X_r positive real syms n_t positive real syms Vs positive real syms x y l...

1 year ago | 0

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Answered
An error 'matlabexecutionerror' occurred when i use 'min' in type optim.problemdef.OptimizationExpression
"min" is not a supported operation for optimization variables: https://uk.mathworks.com/help/optim/ug/supported-operations-on-o...

1 year ago | 0

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How do I make x the subject of this function?
D = 0.05; Y = 0.2170535; f = @(X) Y - (D^2 * acos(1-(2*X/D)) - sqrt(X.*(D-X) .* (D-2*X)) / (pi*D^2)); X = 0:0.001:0.025; plo...

1 year ago | 0

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Is there a function to create the P-P plot in Matlab, to compare two cumulative distribution functions against each other?
rng default; % for reproducibility a = 0; b = 100; nb = 50; % Create two log-normal distributed random datasets, "x" and "y...

1 year ago | 1

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Answered
give correction to my code for finding value of three variable by newton rapson iteration.
The residual for your initial guess is [191,44,534], the residual for the last column of Z is [75e-9,10e-9,9e-12]. Thus obviousl...

1 year ago | 0

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Adjacency matrix for ODE45
k = [0,0.1,0.2,0]; reshape(k,2,2) I think you want the reshaped matrix to be reshape(k,2,2).'

1 year ago | 0

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Answered
Numerical solution for the heat equation does not match the exact solution
I cannot believe that the value for alpha has no influence on the solution. So I guess that the exact solution maybe holds for...

1 year ago | 2

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Answered
When i remove the element wise divison of the RLC beacuse RLC is single array it gives me this error Index exceeds the number of array elements. Index must not exceed 1.
You must keep the elementwise division. So Change Kf_LMax = Kf_Max * (RLC / (1 + RLC)); to Kf_LMax = Kf_Max * (RLC ./ (1 + R...

1 year ago | 0

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Computation of left eigenvectors of polyeig
Hint: If you solve for s and x satisfying (A0.'+s*A1.'+...+s^p*Ap.')*x = 0, using polyeig(A0.',A1.',...,Ap.') , it follows...

1 year ago | 0

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Setting linear constraints for fmincon,
If real(gamma) and imag(gamma) are vectors of optimization variables, the constraints PS(gamma) - t <= 0; - PS(gamma) - t <...

1 year ago | 0

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How to plot temperature along a defined line within a 2D temperature field
Does this help ? https://uk.mathworks.com/matlabcentral/answers/52403-plot-solution-of-pde-toolbox-on-a-line-or-submanifold

1 year ago | 0

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Answered
Both function plots start at 1, even though I have time step as t=0:6
Use plot(t,v) plot(t,a) instead of plot(v) plot(a)

1 year ago | 0

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Answered
in this code for finding root by newton raphson method i gave derivative of f in g. instead of giving derivative directly how can i get derivative using any code?
syms x f = x^4-x^2-80; g = jacobian(f); f = matlabFunction(f) g = matlabFunction(g)

1 year ago | 0

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Answered
how to plot two nonlinear functions
x = -10:0.1:10; y = 0:0.1:20; [X,Y] = meshgrid(x,y); Z1 = X.^2+X.*Y-10; Z2 = Y+3*X.*Y.^2-57; % Visualize the two surfaces ...

1 year ago | 2

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Using symbolic solver, I seem to not be able to get a system of equations that give me a desired answer. Does a solution not exist?
It's the same situation as in your other problem: https://uk.mathworks.com/matlabcentral/answers/2138791-how-can-i-find-a-uniqu...

1 year ago | 1

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2nd Order Polynomial Coefficient Solving
I don't see R in your regression equation T = a + b*P + c*S + d*S^2 + e*(S*P) + f*(s^2*P) And I assume that "s" means "S". M ...

1 year ago | 2

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Answered
limited integration with respect to x in Simulink
As far as I can see, the integral is of the form integral_{x=0}^{x=L} dx / (a*x+b) for some constant values a and b. The anti...

1 year ago | 0

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Routh-Hurwitz criterion
Roots of a general polynomial of degree 6 cannot be explicitly computed. You must give numerical values to a,b,c,d,e and f and u...

1 year ago | 0

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Answered
paretosearch does not satisfy nonlinear constraints
You may get feasible initial points if you run this code before calling "paretosearch" (maybe for different x0 to get several fe...

1 year ago | 1

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Answered
When does an ODE integrator reach the best numerical accuracy?
Solve the problem for different error tolerances and see when the solution stabilizes. If available, also test different solve...

1 year ago | 1

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Plot grraph , srink is problem
I don't know what you mean by "I want to change the Y axis value so that the box and plot on x -axis does concide". Maybe like...

1 year ago | 0

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double and triple integral for a complex function. I coded but did not get any output
According to the literature, the Monte Carlo Integration method seems to be the usual approach: https://iopscience.iop.org/arti...

1 year ago | 0

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Answered
How to update a function with output from another function?
% Solve the coupled ODEs and PDE [t, y] = ode45(@(t, y) odes(t, y, R, C_p_gas, k_liner, k_CFRP, rho_liner, rho_CFRP, C_p_liner,...

1 year ago | 0

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Unable to recognise function from called script
The script should be t = [1, 2, 3, 4]; y = lab1_function(t,0.1) the function should be function y = lab1_function(t, c) y...

1 year ago | 1

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