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getting singular jacobian error while using bvp4c solver
I can't interprete your solution curves, but it seems to be a problem for the solver that the Scaled Mass goes to 0 with increas...

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Empty sym: 0-by-1 : Don't understand why
I multiplied by the denominators and squared to get rid of the square roots. Your system seems to have 4 (complex-valued) solut...

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Non-linear least squares estimation with linear constraints in Simulink?
I vaguely remember that using "lsqcurvefit" within Simulink requires to use the Levenberg-Marquardt algorithm. I can't answer wh...

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Do I have a convergence issue?
B0 = 0.5; B = fsolve(@fun,B0) function residual = fun(B) g = 10; %m/s^2 Q = 70*1000; %N/m tau_L1 = 24*1000; %Pa t_w = 30...

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HOw to find displacement integrating velocity?
The equation from above describes the stationary velocity profile over the length L. Thus replacing v by dx/dt does not make sen...

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Integration symbiolic form in matlab gives error
I think you will have big problems if you try to integrate a function with values in the order of +/- 1e70. syms r theta Part_...

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Why the symbolic method fail when I tried to expand a ellipse
I get the correct result (at least for coe = [1;1;1;1;1;1]) : aex = expandA(ones(6,1)).' function aex = expandA(coe) A = co...

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Why did i receive error with my for loop ode45 function?
I used numerical values for L1, L2, mblade, kt and Jblade right from the beginning and got expressions for dL_dtheta2_numeric an...

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Why do i get the error (Array indices must be positive integers or logical values) when trying to calculate the determinant
I don't get any error. But you shouldn't overwrite the function "det" by using the variable name "det" for the result. Name it ...

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having if/else statement go to previous input
r = rand(); if opt == 1 || (opt == 3 && r < 0.5) abc else xyz end

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6x6 system of multivariate quadratic equations ... non-negative real solutions
I think there is no specialized solver for a system of quadratic equations. Thus a general nonlinear solver ("fsolve","lsqnonlin...

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Color Burr distribution function line
pd = makedist('Burr','alpha',1,'c',2,'k',5); R = random(pd,100,1); pd = fitdist(R,'Burr'); figure(1) plot(pd) x = 0:0.01:2;...

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Writing ODE equations for ode45 to solve;
The form of the equations that can be solved by ode45 is M*y'(t) = f(t,y). So you can decide whether you choose M to be the iden...

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How to use a solver to get the terminal velocity of a sphere.
v0 = fsolve(@fun,1) function res = fun(v0) d_p =...; rho_air = ...; nu_air = ...; rho_w = ...; g = ...; Re ...

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Nusselt number and skin friction for bvp4c
Nu1 = -(1+bk*(1+m))*S1.y(5,1) Nu2 = -(1+bk)*S1.y(5,end) Tau1 = (1-bv*(1+m))*S1.y(4,1) Tau2 = (1-bv)*S1.y(4,end)

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K Nested For Loops for arbitrary K
I'd generate all possible k-tuples out of the n numbers and throw away those that are not monotonic by using the "diff" command:...

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How to find non-zero solutions to underdetermined systems of equations
The null() function gives you a basis for ker(A): A=[0.719600000000000,0.069400000000000,0.526400000000000,0.110700000000000;1....

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How to get the exact step size used by ode45?
If the stepsize is part of the ODE equation, you cannot use ODE45 to solve. You have to write your own integrator.

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Optimization Eigenvalue problem Stiffness matrix
Should be % Perform optimization [K_opt_vec,~,res] = lsqnonlin(@(K) obj_function_reshaped_matrix(K, M, f_exact_Hz), [k1_guess,...

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MATLAb Solve function not solving
Which MATLAB version are you using ? R2024b gives a direct answer: clear all close all syms I1 I2 V0 s=2; eqns=[5*I1+4*...

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how can I calculate euler constant
g = vpa(eulergamma())

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How to find the equation of a 2D plane that best fits a set of vectors defined in n dimensions?
https://stackoverflow.com/questions/48200261/fit-plane-to-n-dimensional-points-in-matlab

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How to obtain direct symbolic solutions without introducing intermediate variables like z and z1 in MATLAB's solve function?
If it can't, I want to see what is the z and z1 in the solution. k,l,x,z and z1 are arbitrary numbers that satisfy joint_soluti...

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How to Set a Minimum Step Size for Variables in GA Solver (Global Optimization Toolbox)?
Define 21 integer variables x_i that can take values 0 or 1 (by using the "intcon" input to "ga" and setting the lower and upper...

fast 2 Jahre vor | 0

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Trying to create a polynomial using data from a table
You can't expect exact agreement, but the approximation is not that bad (at least for the point chosen): % Data preparation dP...

fast 2 Jahre vor | 0

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Algebraic variable derivatives in the DAE solution process
0 = dg/dx * x' + dg/dy * y' + dg/du * u' = dg/dx * f + dg/dy * y' + dg/du * u' Solve for y'.

fast 2 Jahre vor | 0

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System of state dependent delay equations causes ddesd to run forever.
y(5) is negative shortly after t = 0. Thus your delay d = t - y(5) in principle would refer to values of y(1) that are not yet k...

fast 2 Jahre vor | 0

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Integrating multivariate Gaussian pdf in 4 dimensions
Use "mvncdf": https://uk.mathworks.com/help/stats/mvncdf.html If your function is more complicated than posted, try "integralN...

fast 2 Jahre vor | 0

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The mean function isn't working and i don't know why
Check whether the data type of Data_IV_KE is "double". To this end, MATLAB should return "double" when you type class(Data_IV...

fast 2 Jahre vor | 0

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Solving Second-Order BVP with unknown Constants using fsolve
solinit = bvpinit(linspace(-6.17415,6.17415,64),[0;0],[.809827,0]); sol = bvp4c(@mat4ode,@mat4bc, solinit); xint = linspace(...

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