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constrained optimization with Matlab, symbolic function

If your function f is symbolic, you first have to convert it to a numerical function by using "matlabFunction". k_tot = ...; a...

constrained optimization with Matlab, symbolic function

If your function f is symbolic, you first have to convert it to a numerical function by using "matlabFunction". k_tot = ...; a...

12 jours il y a | 0

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I am unable to find the minimum value of function f in this optimization problem. The solver always returns 0 for all variables which is not possible. I am unable to correct.

The solution is correct: A*x <= b is satisfied, and since all elements in the f-vector are positive, 0 is optimal. Maybe you wa...

I am unable to find the minimum value of function f in this optimization problem. The solver always returns 0 for all variables which is not possible. I am unable to correct.

The solution is correct: A*x <= b is satisfied, and since all elements in the f-vector are positive, 0 is optimal. Maybe you wa...

12 jours il y a | 0

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int function is not working properly in matlab

Evaluate gamma(n_star_D3(i)+l_d+1) gamma(n_star_D3(i)-l_d) and you will see the reason. Consequently, Gff_D3(i)...

int function is not working properly in matlab

Evaluate gamma(n_star_D3(i)+l_d+1) gamma(n_star_D3(i)-l_d) and you will see the reason. Consequently, Gff_D3(i)...

13 jours il y a | 0

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Negative sign produced by "functionalDerivative" - why?

As you can see here at the bottom of the page https://uk.mathworks.com/help/symbolic/sym.functionalderivative.html functionalD...

Negative sign produced by "functionalDerivative" - why?

As you can see here at the bottom of the page https://uk.mathworks.com/help/symbolic/sym.functionalderivative.html functionalD...

13 jours il y a | 0

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fmincon get the wrong answer

Cost of buy with price 26 is 2*26 + c = 152 in your setting. Note that although you don't generate energy, Cg_i(0,a,b,c) = c - t...

fmincon get the wrong answer

Cost of buy with price 26 is 2*26 + c = 152 in your setting. Note that although you don't generate energy, Cg_i(0,a,b,c) = c - t...

14 jours il y a | 1

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Why the results of three codes with the same expression and method are different ?

Integrate equation (1) from x = 0 to x = x, and the problem will become much easier. dvdx0ini = 1; St = [0.1,0.5,1]; hold on ...

Why the results of three codes with the same expression and method are different ?

Integrate equation (1) from x = 0 to x = x, and the problem will become much easier. dvdx0ini = 1; St = [0.1,0.5,1]; hold on ...

15 jours il y a | 0

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Curve fitting and parameter estimation with lsqcurvefit

% Load data data = readtable('infections.csv'); dates = datetime(data.Date, 'InputFormat', 'dd-MMM-yy'); cases = data.Cases; ...

Curve fitting and parameter estimation with lsqcurvefit

% Load data data = readtable('infections.csv'); dates = datetime(data.Date, 'InputFormat', 'dd-MMM-yy'); cases = data.Cases; ...

16 jours il y a | 0

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How to set lower bound lb as a function of optimization variable.

Use function "nonlcon" to define nonlinear equality and inequality constraints. If v(i) depends linearly on the solution variab...

How to set lower bound lb as a function of optimization variable.

Use function "nonlcon" to define nonlinear equality and inequality constraints. If v(i) depends linearly on the solution variab...

16 jours il y a | 2

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When using 'quadprog' how do I limit certain solutions so that they can only become whole numbers?

https://uk.mathworks.com/matlabcentral/answers/660423-can-i-solve-mixed-integer-quadratic-programming-miqp-problems-in-matlab-us...

When using 'quadprog' how do I limit certain solutions so that they can only become whole numbers?

https://uk.mathworks.com/matlabcentral/answers/660423-can-i-solve-mixed-integer-quadratic-programming-miqp-problems-in-matlab-us...

17 jours il y a | 0

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Synthax for equation in script

r0 = 3; r1 = 4; delta = linspace(-r0,r0,31).'; k = linspace(-r1,r1,31).'; 0.5*sqrt((delta+k.^2).^2+4*k.^2)

Synthax for equation in script

r0 = 3; r1 = 4; delta = linspace(-r0,r0,31).'; k = linspace(-r1,r1,31).'; 0.5*sqrt((delta+k.^2).^2+4*k.^2)

17 jours il y a | 0

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Equal arc discretization method code

warning("off") syms t t1 t2 % Parameters R2 = 12; %outer radius (between this radius and R1 is constant arc increment) b = 2...

Equal arc discretization method code

warning("off") syms t t1 t2 % Parameters R2 = 12; %outer radius (between this radius and R1 is constant arc increment) b = 2...

17 jours il y a | 0

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A quatity is being solved by a self consistent integration

format long syms x A = 2000; a = 500; b = 1000; Z = 0; for i=1:20 f = x^4*((A^2+Z^2)/(A^2+4*(x^2+a^2)))^4 / (sqrt(x^2+...

A quatity is being solved by a self consistent integration

format long syms x A = 2000; a = 500; b = 1000; Z = 0; for i=1:20 f = x^4*((A^2+Z^2)/(A^2+4*(x^2+a^2)))^4 / (sqrt(x^2+...

17 jours il y a | 0

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How can I write the term \sum_{q=1}^{m} b_{pq}(t)g_q(y_q(t-\tau_{q}(t))) to produce the same graph

I don't know exactly what you are asking for, but if it's about solving Equation 1, you will have to use a solver for delay diff...

How can I write the term \sum_{q=1}^{m} b_{pq}(t)g_q(y_q(t-\tau_{q}(t))) to produce the same graph

I don't know exactly what you are asking for, but if it's about solving Equation 1, you will have to use a solver for delay diff...

18 jours il y a | 0

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Non linear fitting with 3 independent variables

M = load("Data.mat"); fun = @(A,B,C,E)(A - B*M.IL - C*M.a).*exp(-E*M.Vf); f = @(A,B,C,E) fun(A,B,C,E) - M.K; A0 = 13.5*13.2; ...

Non linear fitting with 3 independent variables

M = load("Data.mat"); fun = @(A,B,C,E)(A - B*M.IL - C*M.a).*exp(-E*M.Vf); f = @(A,B,C,E) fun(A,B,C,E) - M.K; A0 = 13.5*13.2; ...

18 jours il y a | 1

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Finite Difference Method - Central Difference Method for Groundwater Flow Problem

It would help if you included the mathematical description of your problem in order to compare with your coding (equation(s) to ...

Finite Difference Method - Central Difference Method for Groundwater Flow Problem

It would help if you included the mathematical description of your problem in order to compare with your coding (equation(s) to ...

18 jours il y a | 0

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How to return a vector output when a vector input is given to a function_handle representing a constant function?

This works in both cases: % Usual Case syms x; syms t; u = symfun(x^2,x); u_x = diff(u,x); u_x = matlabFunction(u_x); u_...

How to return a vector output when a vector input is given to a function_handle representing a constant function?

This works in both cases: % Usual Case syms x; syms t; u = symfun(x^2,x); u_x = diff(u,x); u_x = matlabFunction(u_x); u_...

19 jours il y a | 0

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Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.

Only a single number can be saved in an array element. But you try to save a vector ([a b(i) c 0 0 0 0 0 d(i)]) in a single e...

Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.

Only a single number can be saved in an array element. But you try to save a vector ([a b(i) c 0 0 0 0 0 d(i)]) in a single e...

20 jours il y a | 0

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Runge Kutta 4th Order Method for an Equation

Write a function function dy = f(t,y) that accepts t and a vector y of length 2*n with y = [c_1;...;c_n,cbar_1;...;cbar_n] ...

Runge Kutta 4th Order Method for an Equation

Write a function function dy = f(t,y) that accepts t and a vector y of length 2*n with y = [c_1;...;c_n,cbar_1;...;cbar_n] ...

20 jours il y a | 1

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How can I calculate the integral of Legendre function P(n,theta) ?

The Legendre function is a numerical, not a symbolic function in MATLAB. Further, it's define for -1 < x < 1. So integration f...

How can I calculate the integral of Legendre function P(n,theta) ?

The Legendre function is a numerical, not a symbolic function in MATLAB. Further, it's define for -1 < x < 1. So integration f...

21 jours il y a | 1

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Plotting discrete Klein - Gordon equation (DKG) with friction in DNA

acceleration(1) = acceleration(numBases) = 0 for every value of i in your loop. From the equation initialVelocities = initia...

Plotting discrete Klein - Gordon equation (DKG) with friction in DNA

acceleration(1) = acceleration(numBases) = 0 for every value of i in your loop. From the equation initialVelocities = initia...

21 jours il y a | 0

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Trying to solve system of PDE by spacial discretization. Errors are coming frequent . what am i doing wrong ?

Technically, your code works now. But you get NaN values for some dydt's. The reason might be that you start with a complete 0 v...

Trying to solve system of PDE by spacial discretization. Errors are coming frequent . what am i doing wrong ?

Technically, your code works now. But you get NaN values for some dydt's. The reason might be that you start with a complete 0 v...

21 jours il y a | 0

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I need help with an error I get

Define F before you call "funcao_forca". It's not set in your code. Maybe you mean F = funcao_forca(t,f); because f is a give...

I need help with an error I get

Define F before you call "funcao_forca". It's not set in your code. Maybe you mean F = funcao_forca(t,f); because f is a give...

21 jours il y a | 1

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Error in untitled22>solveHeatEquation1D (line 32) U(N+2,n+1) = beta(t); Error in untitled22 (line 11) [t, x, U] = solveHeatEquation1D(T, a, b,mu, u0,alpha, N, M);

a = 0; b = 1; % spatial interval T = 0.4; % end time mu = 0.5; % conductivity alpha = 1; ...

Error in untitled22>solveHeatEquation1D (line 32) U(N+2,n+1) = beta(t); Error in untitled22 (line 11) [t, x, U] = solveHeatEquation1D(T, a, b,mu, u0,alpha, N, M);

a = 0; b = 1; % spatial interval T = 0.4; % end time mu = 0.5; % conductivity alpha = 1; ...

22 jours il y a | 0

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Why does the code always return "-ve" values?

When I run the main, it returns me all negative values though I have given only two negative values. Why not ? The objective is...

Why does the code always return "-ve" values?

When I run the main, it returns me all negative values though I have given only two negative values. Why not ? The objective is...

22 jours il y a | 0

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gradient descent optimization doesnt work in code?

My guess is that either "Energyconsumption" depends discontinuously on waypointTimes, that epsilon in the compuation of the grad...

gradient descent optimization doesnt work in code?

My guess is that either "Energyconsumption" depends discontinuously on waypointTimes, that epsilon in the compuation of the grad...

22 jours il y a | 0

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Do you need to initiate symbolic variables in a script if you will be calling for a function using those symbolic variables?

You need to define all variables in the calling program that are not being explicitly passed from the function, but that you hav...

Do you need to initiate symbolic variables in a script if you will be calling for a function using those symbolic variables?

You need to define all variables in the calling program that are not being explicitly passed from the function, but that you hav...

22 jours il y a | 0

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Vector with symbolic variable

Works for me. psi = sym('psi',[8 1]); t = 1:1000; psi(t(5))

Vector with symbolic variable

Works for me. psi = sym('psi',[8 1]); t = 1:1000; psi(t(5))

22 jours il y a | 0

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4.2 Whiteboard Coordinate System Error for Function

This arithmetic operation is not defined in MATLAB: 2\*pi

4.2 Whiteboard Coordinate System Error for Function

This arithmetic operation is not defined in MATLAB: 2\*pi

23 jours il y a | 1

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Error: File: untitled5 Line: 19 Column: 1 Function definitions in a script must appear at the end of the file. Move all statements after the "f" function definition to before

Your interval of integration is complex-valued. I used nested functions to make the parameter g visible in your "f". And I ass...

Error: File: untitled5 Line: 19 Column: 1 Function definitions in a script must appear at the end of the file. Move all statements after the "f" function definition to before

Your interval of integration is complex-valued. I used nested functions to make the parameter g visible in your "f". And I ass...

23 jours il y a | 0

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Error using fmincon and integral2: taking integral variables theta and p as an array while performing computation

Take care that you pass k, c and d1 as values, not as function handles to your objective function. Thus (as in all your questio...

Error using fmincon and integral2: taking integral variables theta and p as an array while performing computation

Take care that you pass k, c and d1 as values, not as function handles to your objective function. Thus (as in all your questio...

24 jours il y a | 0

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