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optim.problemdef.OptimizationProblem/solve SOLVE requires a non-empty initial point structure to solve a nonlinear problem.
My advice is: Do what the error message tells you to do and supply an initial point structure to make MATLAB happy. initial.e =...

3 years ago | 0

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how to remove error form BVP4C code
The odes you want to solve cannot be defined in two separate ODE functions. If you want to solve two differential equations sim...

3 years ago | 0

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Answered
fplot showing different curve to plot
plot(p_a,Q) instead of plot(Q,p_a): M = 100; p_b = 2; Q = @(p_a) M./(p_a + p_b); hold on fplot(Q, [0 35]) ylim([0 ...

3 years ago | 0

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Numerical solution to a larger equation.
What is the zero of your choice ? fun = @(lamda2)sinh(5.9605e-08*(((1.1259e+15*lamda2^2 + 7.5126e+15)^2)^(1/2) + 7.5126e+15)^(1...

3 years ago | 0

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What is wrong with my code, my equation is vdv/dy=-G*M/(y+R)^2 ?
syms G M R y v(y) Dv = diff(v,y); eqn = diff(v,y,2) == -G*M/(y+R)^2; cond = [v(0)==100,Dv(0)==0]; sol = dsolve(eqn,cond) Gn...

3 years ago | 0

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How to compare elements of two vectors in MATLAB ?
A = [1 2; 3 4]; B = [1 4; 3 5]; sum(A(:)~=B(:))

3 years ago | 0

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Answered
Problem with time steps in Runge-Kutte method
vx(i+1) = vx(i) + (1/6)*(K1(2)+2*K2(2)+2*K3(2)+K4(2))*h; vy(i+1) = vy(i) + (1/6)*(K1(4)+2*K2(4)+2*K3(4)+K4(4)...

3 years ago | 1

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Travelling salesman problem - Dimension of arrays issue
To concatenate the three vectors, sqrt((Min_Dist(:,2)-SortedCoordinates(i,2)).^2+(Min_Dist(:,3)-SortedCoordinates(i,3)).^2) C...

3 years ago | 0

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Answered
How to compute the double integral over dx and dy?
dx = 0.1; x = -0.5:dx:0.5; dy = 0.1; y = -0.5:dx:0.5; N = length(x); a = randn(N,N); b = randn(N,N); F = (a-b).^2; % Use...

3 years ago | 0

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find equilirium point with all parameter known
I don't know if this solves your problem, but of course you have to reverse the order of the commands here: if (hdot(4)<0) ...

3 years ago | 0

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Curve fitting the data series
The function you define as fitting function tends to Rdc + R1 + R2 + R3 + R4 + R5 as f tends to infinity very fast. In contrast...

3 years ago | 0

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Using fsolve for a set of complex equations
If you want to define K_step*X_step-F_step as a function handle, you will have to define all expressions involving components of...

3 years ago | 0

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how to find equlibrium point of 5 non linear system with numerical method
I don't know if the result is as expected. format long yequi = fsolve(@fun,rand(5,1)) fun(yequi) function dydt = fun(y) e...

3 years ago | 0

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Answered
Array indices must be positive integers or logical values.
H(0) does not exist in MATLAB. Array indices start with 1. And if inv(K-W^2*M) is a matrix, you cannot save it in a scalar H(W)...

3 years ago | 0

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Help with implicit functions in vector form
I have no clue why this happens since the two expressions are exactly the same. The reason is that [x y 1]*w' cannot be evaluat...

3 years ago | 0

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Please Help using fsolve (error)
f1 = (5+x1+x2)/(50-2*x1-x2)^2/(20-x1) - 4e-4; f2 = (5+x1+x2)/(50-2*x1-x2)/(10-x2) - 3.7e-2; f=[f1;f2] And it seems that you d...

3 years ago | 0

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Extra variable in differential equation's symbolic solution
ans1=dsolve(eqn2,'MaxDegree',3) gives the explicit (complicated) solution. For each t, root(...) means the root of the polynom...

3 years ago | 1

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Initial conditions for PDEPE
Maybe you could add a little diffusivity to the components with spurious oscillations (those with f=0). If this is not possible:...

3 years ago | 1

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Goodness of fit for a Zipf distribution
I set up the maximum likelihood function for your data and came up with an estimated value of s = 2.116 for the distribution par...

3 years ago | 1

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Problem solving simultaneous ODEs using 4th order Runge-Kutta method (Too many input arguments.)
I changed (1./(1+(1/B).*C22d)).*(-c1.*(K22.*vy)); to (1./(1+(1/B).*C22d)).*(-c1.*(K22d.*vy)); in the definition of fvy. And...

3 years ago | 0

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incorrect number or types of inputs or outputs for function 'int'
% Define the parameters of the signal A = 1; % Amplitude T_0 = 4*pi; % Period syms t % Generate the signal ...

3 years ago | 0

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Answered
How to solve system of ODE's with Boundary Conditions using BVP4C? (I would be very helpful for you)
Your remaining task: A loop over the values of M. M = 1.0; bvpfcn = @(x,y)[y(2);y(3);-y(1)*y(3)+y(2)^2+M*y(2);2*y(3)+2*y(1)*y(...

3 years ago | 1

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How to solve a system of three coupled vectorized second order ODEs
System to solve for r1=(r1x,r1y,r1z) is: dr1x/dt = v1x dv1x/dt = K1*(m2*(r1x-r2x)/((r1x-r2x)^2+(r1y-r2y)^2+(r1z-r2z)^2)^1.5 + ...

3 years ago | 0

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how to combine matrices
I think you mean xp1 = rand(2,3); xp2 = rand(4,5); xp3 = rand(1,4); xp4 = rand(12,18); szx1 = max([size(xp1,1),size(xp2,1),...

3 years ago | 0

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Why does it give me errors during numerical integration?
T0=1;Hrxn=1;CpSum=1;K0=1;E0=1;R=1;FA0=1;FB0=1;FC0=1;FD0=1;thetaB=1;thetaC=1;thetaD=1;FT=1; T = @(x) T0 + (-Hrxn)./(CpSum).*x; ...

3 years ago | 0

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Answered
Index exceeds the number of array elements. Index must not exceed 10000.
My guess is that "Ytrain" has less than "len" elements. To confirm this, add the lines disp(len) disp(size(Ytrain)) after th...

3 years ago | 0

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Answered
Estoy intentando acceder a los costos de las licencias para matlab
Contact Sales: https://de.mathworks.com/company/aboutus/contact_us/contact_sales.html

3 years ago | 0

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REQUIRE CODE FOR PARAMETER IDENTIFIABILITY FOR ODE BASED MODEL HAVING KINETIC PARAMETERS.
Take a look at https://de.mathworks.com/matlabcentral/answers/1933060-find-kinetic-constants-from-differential-equations?s_tid=...

3 years ago | 0

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Answered
Getting Error Codes, not exactly sure what they mean or how to fix them, please help
% Define circuit parameters Vin_rms = 120; % V Vout = 2.4; % V Iload = 25e-3; % A Vripple = 0.12; % V R2 = 1e3; % Ohm...

3 years ago | 0

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I am trying to get the answer for the sum to infinity for a geometric series. My output should be 3/2 and a loop should be used. I've done that but it won't work. Please help
Sum2Infinity = 0.0; for i = 0:1:10000 Sum2Infinity = Sum2Infinity + FirstTerm * CommonRatio^i; end

3 years ago | 0

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