sol2 = bvp4c(@bvpexam2, @bcexam2, sol);
Ibrardual() function Ibrardual Nt=0.5; Nb=0.5; Le=2; Pr=1; Alpha=[-0.2138;-0.4]; s=1; A=1; %% solution in structure form %...

15 dagar ago | 0

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What is the most computationally efficient factorization of a matrix A?
Prove that the matrix is positive definite and count the number of FLOPs of Cholesky compared to the other factorizations. Sect...

16 dagar ago | 0

what is the error here?
The error is that the parameter "S" is not an input to function "odeBVP" and thus undefined in f =[y(2);y(3);(1/3)*D1*((y(2)^2...

17 dagar ago | 0

Runge kutta giving complex numbers
It doesn't make sense to use such discontinuous input data for the solution of a differential equation. Solving a differential ...

19 dagar ago | 0

How does Matlabs Symbolic Math Toolbox always finds an analytical eigendecomposition for arbitrary polynomial matrices?
For me this begs the question, is the eigenvalue polynomial from eig(...) truly analytic? What do you mean for a polynomial to ...

19 dagar ago | 1

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Want to understand how to implement in matlab the following differential equation?
If you know P1 over time, you don't have a differential equation, but simply an algebraic relation to determine Q: Q = (P1-P2)/...

19 dagar ago | 0

Coding the Thomas algorithm for a heat and mass transfer problem
When I run the function, I get: Not enough input arguments. Error in solvePDEs (line 27) y(n) = linspace(y_span(1), y_s...

20 dagar ago | 1

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Mapreduce with tall array in matrix multiplication
Would this work for you ? B = ones(2,3); A = tall(ones(200,2)); values = A*B; gather(values)

20 dagar ago | 0

Does pdepe accept 'Vectorized', 'on' as an option? If so, what does it do?
If you look into the documentation for "pdepe", you will find that the "Vectorized" option cannot be chosen: Cited from the doc...

21 dagar ago | 0

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Complex Integration in MATLAB with symbolic integration limits
Does this help ? Note that no distiction is made about the R-value. But you should keep in mind that the answer is incorrect i...

21 dagar ago | 0

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how i can change column vector into row vector??
Simply converting a row vector into a column vector needs the usual transpose operator which is .' You used only ' with is conju...

23 dagar ago | 0

Does cummax works in a sde solver?
My question is: does here cummax works on all previous values of X(2)-X(1), or it takes it as a scalar at every iteration? It t...

23 dagar ago | 0

H have a error in FDM.
F(i+1) = (F(i) + F(i+2))/2 -H(i)*(h/2)*(F(i+1)-F(i)) +(h^2)*(G(i)^2) - (h^2)*(F(i)^2) + (h^2)*(S/2)*((((i*h)+1)/2)*((F(i+...

23 dagar ago | 0

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Error using matlab.internal.math.interp1 Input coordinates must be real.
For some reason, the k suggested by "fminbnd" becomes complex-valued so that interpolation in function "valfunsto" is no longer ...

23 dagar ago | 0

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Computing Partial derivates of anonymous functions comprised of sum of standard functions
Your code works for me. Maybe you have a MATLAB version where the second argument to "diff" is only interpreted as the order of ...

24 dagar ago | 0

Computing Partial derivates of anonymous functions comprised of sum of standard functions
Stay numerical in your computation and approximate the gradient of your objective function "obj" by finite-difference quotients:...

24 dagar ago | 0

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How do I optimize/find the minimum of a multi-variable function?
If you don't restrict your x- and y- variables to certain lower and upper bounds, the minimum of the function your get from "fit...

25 dagar ago | 0

Can I use fmincon with a whole model as function?
I don't see your problem. You call "fmincon" as sol = fmincon(@fun,x0) and write a function "fun" as function obj = fun(x) ...

25 dagar ago | 0

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Regarding choosing correct boundary condition
If you set qL = 1 and qr = 1 and you defined f as f = D*du/dx in the function where you need to specify [c,f,s], you can specify...

25 dagar ago | 0

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How to interpolate 2-parameter dependents matrices?
Use griddedInterpolant or scatteredInterpolant on each matrix element separately depending on whether the point pairs (Vi,qj) fo...

25 dagar ago | 0

Mathematical Equations to MATLAB
%Parameters beta = 2; alpha = 200; Ccl = 2000; Cpm = 2500; Rl = 1100; Cren = 50000; delta = 0.223; P = 12; N = 8; Clo...

26 dagar ago | 0

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How can I replace NaN in a table with a zero?

26 dagar ago | 0

ODE15i DAE Warning:Failure at t=0.000000e+00. Unable to meet integration tolerances without reducing the step size below the smallest value allowed (0.000000e+00) at time t.
It can be deduced from your equations that the only possible solution for your DAE system is y(i) = 0 for i=1,...,8. Thus you c...

27 dagar ago | 0

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Solver Stop Prematurely as new equation added
Use an options structure for "fsolve" as options = optimset('MaxFunEvals',100000,'MaxIter',100000) sol = fsolve(...,options) ...

27 dagar ago | 1

Please tell me what corrections can I make when encountering the following error?
We don't know the contents and sizes of the arrays you use. So we are unable to help. This would work e.g. : xspan = linspace(...

28 dagar ago | 0

Can I solve more than two PDEs in 2D?
If you have a licence for the PDE Toolbox, you can apply it to solve your problem.

28 dagar ago | 0

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Iteration method of optimization
That's what I get from your description. But I might have misunderstood something. % Parameters m_values = linspace(0, 1, 100)...

28 dagar ago | 0

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Error using surf (line 71) Z must be a matrix, not a scalar or vector.
Before your loop insert the commands size(squeeze(ws(:,:,1))') size(we_m) size(sn_m) For surf to work, all sizes must be the...

28 dagar ago | 0