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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...

quasi 2 anni fa | 0

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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;...

quasi 2 anni fa | 0

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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...

quasi 2 anni fa | 0

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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 ...

quasi 2 anni fa | 1

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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)

quasi 2 anni fa | 0

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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:...

quasi 2 anni fa | 0

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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....

quasi 2 anni fa | 0

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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.

quasi 2 anni fa | 0

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Risposto
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,...

quasi 2 anni fa | 0

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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*...

quasi 2 anni fa | 1

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

quasi 2 anni fa | 1

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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

quasi 2 anni fa | 1

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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...

quasi 2 anni fa | 0

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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...

quasi 2 anni fa | 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...

quasi 2 anni fa | 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'.

circa 2 anni fa | 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...

circa 2 anni fa | 0

Risposto
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...

circa 2 anni fa | 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...

circa 2 anni fa | 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(...

circa 2 anni fa | 0

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Risposto
Hi,I tray RUN this code but i get tis error ( below the code)
Variables and/or functions are missing to run your code. According to the error message, m90_plot is an array of size 12784, bu...

circa 2 anni fa | 0

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expressing the complex function
Use syms x t real instead of syms x t Then real(series) and imag(series) will work.

circa 2 anni fa | 0

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beginner integration trouble.
"int" cannot find an analytical antiderivative for f(x). Thus to get the numerical value for the integral, use Area=2*vpainte...

circa 2 anni fa | 0

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How to loop through values?
Beta = linspace(0,1,10); Alpha = linspace(0,2,20); n = numel(Beta); m = numel(Alpha); Result = zeros(n,m); for i = 1:n ...

circa 2 anni fa | 0

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Using erfcinv and array indices are being rejected as not positive or valid, despite all being positive in the vector
As far as I understand, "erfbatp" is an array of numbers. So erfbatp(2*.05/2) = erfbatp(0.05) does not make sense, does it ? V...

circa 2 anni fa | 0

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Converting symbolic ODE solution to function ... Warnings
The solution is implicitly given by the equation (a*y+b*y^2/2+c*y^3/3+d*y^4/4)-(a*y0+b*y0^2/2+c*y0^3/3+d*y0^4/4) - integral_{x'...

circa 2 anni fa | 0

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convert the above expression into this graph
I'll show you how to solve for theta2 given theta from the equation sin(theta2-theta)+exp(-theta2/(omega*tau))*sin(theta)=0 F...

circa 2 anni fa | 1

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Trouble using ODE45 for coupled non-linear differential equation
I can't recover the four differential equations you solve from the two equations you included in mathematical form. Your equati...

circa 2 anni fa | 0

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How to get the answer from the following code. How can i extract the values from the code?
F = U1.y(5,1)-Nt*U1.yp(5,1) J = -1i*U1.y(6,1) N1 = -U1.y(7,1) N2 = -U1.y(8,1)

circa 2 anni fa | 0

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Explicit method for Allen-Cahn equation
xstart = -1.0; xend = 1.0; nx = 401; x = linspace(xstart,xend,nx).'; dx = x(2)-x(1); tstart = 0.0; tend = 1.0; nt = 10; ...

circa 2 anni fa | 0

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