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Numerical error for same MATLAB function but generated differently
General answer for an unspecific question: https://uk.mathworks.com/help/symbolic/choose-symbolic-or-numeric-arithmetic.html E...

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Adding inequality constraints in DAE system
You can't. These problems usually appear in optimal control problems where the DAE integrator is coupled with an optimizer. Par...

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(ASAP)why symsum can not calculation?????
t = -2:0.1:2; a = 1; N = 60; n = (1:N).'; f = sinc(n/2).*cos(2*pi*a*n.*t/4); s = 0.5 + sum(f,1); plot(t,s)

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Solving a system of equtions with first an pde and the others first order odes
"pdepe" does not support pure ODEs together with a partial differential equation with 2nd order derivatives in space. Use "pde1...

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Mackey Glass equation and ddesd
I'm not sure what you are exactly asking for, but for a history v = 0, the solution is v = 0 for all times t > 0. So the plot y...

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Moment of Lognormal distribution
https://math.stackexchange.com/questions/628681/how-to-compute-moments-of-log-normal-distribution or with MATLAB (the second re...

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I don't know why my code makes odeToVectorField error
From the documentation: odeToVectorField can convert only quasi-linear differential equations. That is, the highest-order deriv...

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Pareto frontier plot error
In both examples, the two objective functions are not "competitive" since both have (0/0) as optimum combination for x1 and x2 i...

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Application of any numerical root finding method (secant, bisection, etc.)
Plot first, then solve by using the approximate root as initial guess: Cs = 0; d = 0.5; g = 9.81; %User definition of input ...

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It's a question of finding a static integral There's an error in the formula
integral(@(x)(x+2)./(x+1).^3-exp(-3*(x+3)),0,3) If you cannot input a mathematical formula in MATLAB, I suggest you invest 2 ho...

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How do I solve an equation with an unknown variable?
I always use pencil and paper: v=70 ; ro=1.225 ; Sw=5 ; c=0.5 ; CM_ac = -18/(0.5*ro*(v^2)*Sw*c)

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Creating 'n' matrices with each one with 'n' in its name
YEAR{n} = zeros(DATE_RANGE(n,3));

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Matlab double sum over vectors
Note that -pi<=kx<=pi, -pi<=ky<=pi, -pi<=kx'<=pi, -pi<=ky'<=pi because of your linspace choice. And most probably you need to n...

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Solving symbolic third order polynomial
syms t t0 t1 q0 q1 q0dot q1dot a0 a1 a2 a3 f(t) = a0 + a1*(t-t0) + a2*(t-t0)^2 + a3*(t-t0)^3; df = diff(f,t); S = solve([f(t0...

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The number of rows in A must be the same as the number of elements of b error
% Define the coefficients of the objective function as a double vector c = -[-6, 3, 17, 10, 63, 34, 15, 22, -2, 15, ... ...

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Problem with Curve Fitter 95% CI Upper and Lower Bounds' Equations
Have a read here: https://uk.mathworks.com/help/curvefit/confidence-and-prediction-bounds.html It will show you the difference...

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Error using barrier Objective function is undefined at initial point. Fmincon cannot continue.
If you insert the line augmented_objective(x0) before the call to fmincon, you will see that your objective returns a complex ...

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Solving Pde equation with pdepe solver
If you use the PDE Toolbox, you can define 3d-geometries - if it's that what you mean.

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Function 'quadprogIP' runs fast seperately but extremely slow in a for loop simulation
Maybe the problems to be solved get larger or more complicated within the for loop so that the average time spent for each probl...

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Function "diff" and the loss of an element in the array
Use "gradient" if you don't want to loose elements: https://uk.mathworks.com/help/matlab/ref/gradient.html

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solve ode with ode45
Comment out t = [0 5] before calling ode45 in the loop: %t = [0 5];

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Why does solving my equation result in the message "No complex subexpressions allowed in real mode."?
Next time, please report the real problem right at the beginning. %loading the constants eps_w = load('eps_w.mat'); eps_w = e...

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I want 4 solid lines for Fr paramter . but im getting single line why?
S_a() function S_a %%%%note%%%%%%%%% %%%%%%%%%%%%%%%%% decreasing behaviour with F...

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two layer transient conduction heat transfer with pde
The boundary condition for pdepe reads p + q*f = 0. In your case this leads to hr_int * (urMax - ul) + k1*k1/(rho1*Cp1)*dT/dx...

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solve a second-order differential equation using finite differences, I keep encountering the 'Index exceeds the number of array
Replace your functions by p.m % p.m function result = p(t) result = 2 * t ./ (1 + t.^2); end q.m % q.m function re...

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Why does solving my equation result in the message "No complex subexpressions allowed in real mode."?
Why don't you simply solve for pw ? pw = (eps_exp^(1/3) - eps_l^(1/3))/(eps_w^(1/3)-eps_l^(1/3)) Note that you use eps_w^(1.3)...

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for loop in bvp4c i get circle in plotting not solid line why?
sss() function sss global Fr Pr f2 f1 shi2 shi3 lambda zeta Sk u Re Kf B A H1 H2 H3 C1 C2 C3 P1 P2 P3 K1 K2 K3 Kb n Z ...

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Please help me in solving the given coupled differential equation? Please also tell me the numerical recipe availabe in matlab for handling such equations.
MATLAB has no tools to solve this kind of equations. I guess they are hyperbolic in nature - so take a look at CLAWPACK: https...

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Solve differential and algebraic equation system
S_1 and q_j are symbolic functions. You have to convert them to numerical functions first (by "MatlabFunction") to use them with...

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Trouble printing more than one set of data on plot after solving system of odes
Call ode15s three times: the first time to compute the solution for A and R with M(1), the second time with M(2) and the third t...

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