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Torsten


Last seen: Today Active since 2013

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Answered
how to incorporate boundary conditions as constraints in fmincon optimization?
I think with the mixture of numerical, symbolic and optimization variables it is easier to set up the problem directly. x0 = [ ...

4 hours ago | 0

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Answered
Newtons Method but error message "Singular Matrix"
This is quite a tricky problem - even with the MATLAB solvers available. For given V and theta at t = 0, integrate until x beco...

6 hours ago | 1

Answered
Fsolve Recommending Algorithm I Already Specified
You overwrite the previously set options with this line options = optimoptions('fsolve', 'Display', 'none', 'TolFun', 1e-6, 'To...

10 hours ago | 1

Answered
How can i use this vector in my ODE function?
Integrate from t=0 to t=10 and use u = 30. Restart the ode solver with the solution at t = 10 and integrate from t=10 to t = 20...

1 day ago | 0

Answered
Simulating a 1D Random Walk
% Step 2: Plot the entire trajectory for a single random walk N = 100; % Number of steps single_trajectory = simulateRandomWal...

1 day ago | 0

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Answered
How to plot different length vectors against each other?
However the x vector has a length of 113 compared to 1849 for y because of the differences in timestep. Solve for x and y toget...

1 day ago | 0

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Answered
Error using linprog (line 369)
A_s and f_s are not specified in your code. But without running your code, I think your problem exceeds your available computer...

1 day ago | 0

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Answered
95% confidence bounds from logistic curve (curve fitter) give different results to plotting via equation in script
It's not possible to just insert lower and upper bounds for the parameters into the model equation to get the curves for the con...

1 day ago | 0

Answered
how to calculate the drivative of discretized ODE
After the line sol = ode45(@(t,u) dODE(t, u, par, tau, M,D), tspan, u0,options); you can compute the derivatives of the soluti...

1 day ago | 0

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Answered
There is an error when i run my 'subplot' command in MATLAB
Rename your script file "subplot.m" to something else. "subplot" is a reserved name in MATLAB.

2 days ago | 1

Answered
Please help for objectiveFunction command.
You don't supply k1, k2, c1 and c2 to the objective function. If these are the parameters to be optimized, you don't need to pa...

2 days ago | 1

Answered
1D HEAT CONDUCTION
In each time step, you have to solve the linear system of equations T(1,k+1) = Tleft T(i, k+1) - deltat/deltax^2*alpha* (T(i-...

2 days ago | 1

Answered
Finding a definite integral
x = linspace(0,1,101); u = [0.1600 0.1600 0.1599 0.1599 0.1597 0.1596 0.1594 0.1592 ... 0.1590 0.1...

2 days ago | 0

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Answered
Compute a function that has Double summation
All the series involved are geometric series for which the finite and infinite sums are known: sum_{i=1}^{i=n} q^i = q * (1-q^n...

3 days ago | 0

Answered
What does this mean: K12_global(1:3:6,1:3:6)?
Do you see what happens ? The new matrix K12 is formed of the elements (1,1),(1+3,1),(1,1+3) and (1+3,1+3) of the original mat...

3 days ago | 0

Answered
Unable to meet integration tolerances without reducing the step size below the smallest value allowed (1.136868e-13) at time t.
I had to add the line global alpha pD K g_T IFN at the beginning of your program to make the code work because the above globa...

3 days ago | 0

Answered
Numerical Differentiation using Finite Differences
h = 0.01; x = 0:h:2*pi; fx = sin(x); %df1 = (sin(x+h) - sin(h))/h; df1 = (sin(x+h) - sin(x))/h; df2 = (sin(x) - sin(x-h...

3 days ago | 0

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Answered
Efficiently evaluating ODE event that depends on only some variables
Use OutputFcn to check your condition after each successful time step. But I think it will be difficult to check for complanari...

3 days ago | 0

Answered
Finding real and imaginary part of an equation
U = 0:0.1:10; P = sqrt((((20*U.^2)-15) + sqrt((400*U.^4)+ (1080*U.^2) + 25 -600 - 450 - (1125./U.^2)))./((36*U.^2) + 30)); Pim...

4 days ago | 0

Answered
I have a code related to thermodynamic subject, i don't know how to run it in order to get the different plot out of it. for example plot (p,rho). plot of pressure vs density.
I think there is something wrong in the calculation of the compressibility factor. p = EOS(2.0,150) function p=EOS(rho,temp)...

4 days ago | 0

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Answered
compute sums by accumulating in a for-loop
sum(xprime(1:100-l)) This is a scalar. sum(xprime(1:100-l)).*xprime(1+l:100) This is a vector of length 100-(1+l)+1. (sum(xp...

4 days ago | 0

Answered
Financial optimization of heston
Assuming that Price_SV returns a vector of the same size as P_data, your call would look somehow like fun =@(p)Price_SV(p(1), p...

4 days ago | 0

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Answered
I don't know why this code is saying, "Arrays have incompatible sizes for this operation."
Your vector of initial conditions is 6x1 y0 = [Pi; Si; Li; Ii; Ri; Bi]; but you only return a 5x1 vector in PSLIR dydt = [dPd...

6 days ago | 0

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Answered
Matlab grader discretization help
Use off_diagonal = coefficient * ones(N-1, 1); instead of off_diagonal = coefficient * ones(N-2, 1); See the example "Create...

6 days ago | 0

Answered
Apply fmincon nonlinear parameter inequality constraints into SimBiology for parameterization
function [c,ceq] = nonlincon(params) %Nonlinear inequality constraints c(1) = params(1)*params(2) - params(5)*params(7); % For...

6 days ago | 0

Answered
Trouble with For Loop
for i = 1:35 dataN_(i) = ecg_data (:,i); mean_HR_subject(i) = ... ... end

6 days ago | 0

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Answered
Solving first order ODE with initial conditions and symbolic function
You solved it in your code. The second solution out of the three MATLAB returned is the "correct" one giving real-valued tempera...

6 days ago | 0

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Answered
It takes too long to run the program and in the end I get an error, could you tell me what the error is?
You can't change the input for x in function "campo_pendulo". So you can delete this part of your code because it doesn't influ...

6 days ago | 0

Answered
Can someone help me check if I did this correctly?
Replace syms r a0 by syms r a0 positive to get the limits resolved.

6 days ago | 0

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Answered
Fixed Bed Adsorption Column Using Dimensionless Equations
The usual procedure is to define a grid 0 = X(1) < X(2) < ... < X(n) = 1 approximate the spatial derivative dA/dX in grid poin...

7 days ago | 1

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