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Calculations with distributions of variables only
Look up "Monte-Carlo-Simulation".

1 year ago | 0

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Time-dependent dynamic problem with nonlinear stiffness using ode45
You solve for U and Udot - thus you get values for U and Udot from ode45. Simply compute the matrix K(U) with these values and p...

1 year ago | 0

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Error: Data must be numeric, datetime, duration, categorical, or an array convertible to double.
% Declaring Theta and Phi Variables theta = 0:0.1:pi/2; % Phi Values phi_E_Plane = 0; phi_H_Plane = pi/2; % Declaring x...

1 year ago | 0

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How to solve this differential equation? I got ''Warning: Unable to find symbolic solution.'' error. What am I missing ?
You don't miss anything - your equation is just too complicated to have an analytical solution. You will have to use a numerica...

1 year ago | 0

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Answered
fsolve error: Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.
Include the line size((2.*x_SW(2).*dfreq_SW_vr.*w(1).*g2) + ((1./4).*x_SW(1).*nu).*(f1b.*zet_0_0 + f2b.*eta_0_0).*g1.*cos(gamm...

1 year ago | 0

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Hi All. Just wondering why answer to (i) is not 4.9e+4. an why answer to (iii) is not (9x)/2 or 4.5 x. Many thanks. Brian
For (iii), use syms x real instead of syms x

1 year ago | 1

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Overwriting the maximum function evaluation
You didn't include the structure "optim_lsq" in the call to lsqcurvefit.

1 year ago | 0

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How do you compute the product of a matrix and each column of another matrix without a for loop in MATLAB, or is this just not possible?
y = C*x

1 year ago | 0

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Answered
Operands to the logical AND (&&) and OR (||) operators must be convertible to logical scalar values. Use the ANY or ALL functions to reduce operands to logical scalar values.
if all(abs(grad_g1_val) < tol) && subs(g1, {x1, x2, x3}, x') <= 0 activeSet = [activeSet, 1]; % Constraint 1 is ac...

1 year ago | 0

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Answered
ODE45 and dsolve result difference
dydx(2)=2-2*y(2)-8*x; instead of dydx(2)=2-2*y(2)-8*y(1);

1 year ago | 1

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Answered
Intersection condition between two ellipses
I'm surprised that we get a division by zero by the below solution method if the aspect ratio of the two ellipses is equal. Bu...

1 year ago | 0

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Arrayfun with Extra Parameters
Test3 = arrayfun(f,a,b) instead of Test3 = arrayfun(@f,a,b)

1 year ago | 0

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Answered
Extract the indices based on the minimum absolute value
Maybe you mean %define the number of random numbers n = 10; %define the min and max ranges of random values stvar = [0 4]...

1 year ago | 0

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How to fit a distribution whose parameters depend on other parameters?
In this case, you must assume a parametric expression for T(z) as well (e.g. T(z) = a + b*z) and add a and b to the parameters t...

1 year ago | 0

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Solve and plot system in x and y with varying constants e and t
basically i would like to obtain on the same graph different curves in x and y for a fixed number of combinations of e and t. I...

1 year ago | 0

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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 %...

1 year ago | 0

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Answered
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...

1 year ago | 0

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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...

1 year ago | 0

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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 ...

1 year ago | 0

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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 ...

1 year ago | 1

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Answered
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)/...

1 year ago | 0

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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...

1 year ago | 1

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Answered
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)

1 year ago | 0

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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...

1 year ago | 0

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Answered
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...

1 year 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...

1 year ago | 0

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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...

1 year ago | 0

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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+...

1 year ago | 0

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Answered
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 ...

1 year ago | 0

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Answered
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 ...

1 year ago | 0