Risposto

how to get a good estimate of the positive parameters that will give a good fit of the curves to real data?

You should avoid defining the same data, parameters and variable definitions multiple times in your code (specific_data, gamma, ...

how to get a good estimate of the positive parameters that will give a good fit of the curves to real data?

You should avoid defining the same data, parameters and variable definitions multiple times in your code (specific_data, gamma, ...

17 giorni fa | 1

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Risposto

How can I find a unique solution within tolerance using solve?

As long as rank(A) equals 3 in the below code, your system of linear equations has a unique solution. syms Rx Risop Rison V1=2...

How can I find a unique solution within tolerance using solve?

As long as rank(A) equals 3 in the below code, your system of linear equations has a unique solution. syms Rx Risop Rison V1=2...

18 giorni fa | 0

Risposto

function must return a column vector

Allocate dy as a column vector before assigning values to it: %Ordinary differential equation dy = zeros(4,1); dy(1)=alpha*(1...

function must return a column vector

Allocate dy as a column vector before assigning values to it: %Ordinary differential equation dy = zeros(4,1); dy(1)=alpha*(1...

18 giorni fa | 0

Risposto

I'm having trouble solving a system of nonlinear equations with the fmincon function.

Use % Options for fmincon options = optimoptions('fmincon', 'Algorithm', 'interior-point', 'Display', 'off','ConstraintToleran...

I'm having trouble solving a system of nonlinear equations with the fmincon function.

Use % Options for fmincon options = optimoptions('fmincon', 'Algorithm', 'interior-point', 'Display', 'off','ConstraintToleran...

19 giorni fa | 0

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Risposto

Simulation - number of samples

Is there a preset (optimum) value and how is this determined? As big as necessary and as small as possible. You will have to te...

Simulation - number of samples

Is there a preset (optimum) value and how is this determined? As big as necessary and as small as possible. You will have to te...

19 giorni fa | 1

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Risposto

Need help with homework.

Note that the name of the German physician was Fahrenheit, not Farenheit. % prompt for user to choose which conversion chosen_...

Need help with homework.

Note that the name of the German physician was Fahrenheit, not Farenheit. % prompt for user to choose which conversion chosen_...

20 giorni fa | 0

Risposto

Weird bugs when solving three coupled second order differential equations using ode45

syms x1(t) x2(t) y(t) t0 = [0 1]; % y0 must be given in the order as prescribed by S (see below), thus % y0 = (x2(0),dx2/dt(0...

Weird bugs when solving three coupled second order differential equations using ode45

syms x1(t) x2(t) y(t) t0 = [0 1]; % y0 must be given in the order as prescribed by S (see below), thus % y0 = (x2(0),dx2/dt(0...

20 giorni fa | 0

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Risposto

Bessel function has problems in converting symbolic function into handle function.

It works for the numerical "besselj" function. Its derivative is given here: https://uk.mathworks.com/matlabcentral/answers/93...

Bessel function has problems in converting symbolic function into handle function.

It works for the numerical "besselj" function. Its derivative is given here: https://uk.mathworks.com/matlabcentral/answers/93...

20 giorni fa | 0

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Risposto

Bessel function has problems in converting symbolic function into handle function.

This code seems to work. Can you show us where you encounter problems ? syms x n = 12; f = sqrt(sym(pi)/(2*x))*besselj(n+1/2,...

Bessel function has problems in converting symbolic function into handle function.

This code seems to work. Can you show us where you encounter problems ? syms x n = 12; f = sqrt(sym(pi)/(2*x))*besselj(n+1/2,...

20 giorni fa | 0

Risposto

optimization expression includes an integration

c = optimvar("c",1,1,'Type','continuous','LowerBound',0.1,'UpperBound',10); g1 = @(x,c) exp(-0.5*(x./c).^2)./sqrt(2*pi*c^2); o...

optimization expression includes an integration

c = optimvar("c",1,1,'Type','continuous','LowerBound',0.1,'UpperBound',10); g1 = @(x,c) exp(-0.5*(x./c).^2)./sqrt(2*pi*c^2); o...

20 giorni fa | 1

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Risposto

How can I clear an error "The expression to the left of the equals sign is not a valid target for an assignment?"

You have seven differential equations, but you only specify six boundary conditions. That's mathematically incorrect. plot_velo...

How can I clear an error "The expression to the left of the equals sign is not a valid target for an assignment?"

You have seven differential equations, but you only specify six boundary conditions. That's mathematically incorrect. plot_velo...

20 giorni fa | 0

Risposto

I am getting an error

Do you want to overwrite the MATLAB function "convolution1dLayer" by your own function ? function output = convolution1dLayer(i...

I am getting an error

Do you want to overwrite the MATLAB function "convolution1dLayer" by your own function ? function output = convolution1dLayer(i...

21 giorni fa | 0

Risposto

Why does this code give error?

Force the array ix1 to be of the same length as ix by explicitly allocating it with the size of ix: % Run the GBO algorithm...

Why does this code give error?

Force the array ix1 to be of the same length as ix by explicitly allocating it with the size of ix: % Run the GBO algorithm...

21 giorni fa | 0

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Risposto

Problem Using the Median Function with Complex Numbers

c = a + (b-a)/2; k = (sign(a) ~= sign(b)) | isinf(a) | isinf(b); c(k) = (a(k)+b(k))/2; But in every case, you set...

Problem Using the Median Function with Complex Numbers

c = a + (b-a)/2; k = (sign(a) ~= sign(b)) | isinf(a) | isinf(b); c(k) = (a(k)+b(k))/2; But in every case, you set...

21 giorni fa | 0

Risposto

issue with fmincon function.

I guess the objective function should read obj_fun = @(x) -(Nup - Nt) / Nup * sum(log2(1 + x(1:Ns) ./ (sigma2 * (vecnorm(reshap...

issue with fmincon function.

I guess the objective function should read obj_fun = @(x) -(Nup - Nt) / Nup * sum(log2(1 + x(1:Ns) ./ (sigma2 * (vecnorm(reshap...

21 giorni fa | 0

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Risposto

Index in position 1 exceeds array bounds. Index must not exceed 18.

data = (EEG.icaweights(opt.component,:)*EEG.icasphere)*data(EEG.icachansind,:); You are aware that you overwrite the matrix "da...

Index in position 1 exceeds array bounds. Index must not exceed 18.

data = (EEG.icaweights(opt.component,:)*EEG.icasphere)*data(EEG.icachansind,:); You are aware that you overwrite the matrix "da...

21 giorni fa | 1

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Risposto

How do I construct matrices of multiple variables and plot a graph

tspan=[0 3]; x0=100; y0=0; z0=[x0;y0]; [tSol, zSol]=ode45(@odefun,tspan,z0); plot(tSol, zSol); function dzdt=odefun(t,z) ...

How do I construct matrices of multiple variables and plot a graph

tspan=[0 3]; x0=100; y0=0; z0=[x0;y0]; [tSol, zSol]=ode45(@odefun,tspan,z0); plot(tSol, zSol); function dzdt=odefun(t,z) ...

22 giorni fa | 1

Risposto

I don't know what this means

Most probably, you don't have write permission in the directory to which you want to unzip 'MerchData.zip'.

I don't know what this means

Most probably, you don't have write permission in the directory to which you want to unzip 'MerchData.zip'.

23 giorni fa | 0

Risposto

Coupled ODEs by ode45 and could not get the figures

% Initial conditions Y0 = [298; 0.75; 0.04; 0.015; 0.0331; 0]; % [T0; Xa0; Xc0; Xs0; Z0; Soc0] % Time span tspan = [0 3000]; ...

Coupled ODEs by ode45 and could not get the figures

% Initial conditions Y0 = [298; 0.75; 0.04; 0.015; 0.0331; 0]; % [T0; Xa0; Xc0; Xs0; Z0; Soc0] % Time span tspan = [0 3000]; ...

25 giorni fa | 1

Risposto

Can integral2 left a variable inside?

@Guan Hao You cannot simply remove the w in your expression as suggested by @Umar. I'd do the general integration first and the...

Can integral2 left a variable inside?

@Guan Hao You cannot simply remove the w in your expression as suggested by @Umar. I'd do the general integration first and the...

25 giorni fa | 0

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Risposto

A numerical calculation problem leading to Inf or NaN in matlab

log2(norm(x,lambda)) does not work ?

A numerical calculation problem leading to Inf or NaN in matlab

log2(norm(x,lambda)) does not work ?

25 giorni fa | 1

Risposto

Hello all, kindly, I have question , how can I get the piecewise function of this blood flow rate shown below using Matlab

T = 0.56; A = 220; fun = @(x)A*sin(2*pi*x/T).*(x>=0 & x<=T/2) + 0*(x>T/2 & x <=0.7); F = @(x)fun(mod(x,0.7)); x = linspace(0...

Hello all, kindly, I have question , how can I get the piecewise function of this blood flow rate shown below using Matlab

T = 0.56; A = 220; fun = @(x)A*sin(2*pi*x/T).*(x>=0 & x<=T/2) + 0*(x>T/2 & x <=0.7); F = @(x)fun(mod(x,0.7)); x = linspace(0...

26 giorni fa | 0

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Risposto

calling function from separate document for fitting

However, when I try to call script 1 from 2, I get a ton of error messages. Could I please ask why is this the problem? You ca...

calling function from separate document for fitting

However, when I try to call script 1 from 2, I get a ton of error messages. Could I please ask why is this the problem? You ca...

27 giorni fa | 0

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Risposto

Setting bounds for constants in a fit() object in terms of other constants in the fit object

Use "lsqcurvefit" and set A(1,2) = -1, A(1,3) = 1/min(x) and b(1) = 0 for the linear constraint condition A*x<=b.

Setting bounds for constants in a fit() object in terms of other constants in the fit object

Use "lsqcurvefit" and set A(1,2) = -1, A(1,3) = 1/min(x) and b(1) = 0 for the linear constraint condition A*x<=b.

27 giorni fa | 1

Risposto

How store evolution of x over the iterations of lsqnonlin?

If you can't use the nested approach, define "history" as a persistent variable and call "myoutput" after the computation has fi...

How store evolution of x over the iterations of lsqnonlin?

If you can't use the nested approach, define "history" as a persistent variable and call "myoutput" after the computation has fi...

27 giorni fa | 1

Risposto

Something doesn't work for me in fit

hist_x=[10 30 50 70 90 110 130 150 170 190 210 230 250,... 270 290 310 330 350 370 3...

Something doesn't work for me in fit

hist_x=[10 30 50 70 90 110 130 150 170 190 210 230 250,... 270 290 310 330 350 370 3...

28 giorni fa | 0

Risposto

simplify and reorganize symbolic expression

The only symbolic function that comes to mind is "coeffs". If this function does not do what you want, I fear you are lost here....

simplify and reorganize symbolic expression

The only symbolic function that comes to mind is "coeffs". If this function does not do what you want, I fear you are lost here....

29 giorni fa | 0

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Risposto

help with bvp4c error

Use solinit = bvpinit(x_init,[1 1 phi_c 0]); instead of solinit = bvpinit(x_init,[1 1 phi_c 0],w); Why did you use the w-pa...

help with bvp4c error

Use solinit = bvpinit(x_init,[1 1 phi_c 0]); instead of solinit = bvpinit(x_init,[1 1 phi_c 0],w); Why did you use the w-pa...

30 giorni fa | 0

Risposto

Index in position 1 is invalid. Array indices must be positive integers or logical values Error

Array indexing in MATLAB starts with 1, not with 0. But you try to set Pdata(0)=pressure01(0,1); in your nested loop for i = ...

Index in position 1 is invalid. Array indices must be positive integers or logical values Error

Array indexing in MATLAB starts with 1, not with 0. But you try to set Pdata(0)=pressure01(0,1); in your nested loop for i = ...

circa un mese fa | 0

Risposto

Is this a correct way to use fsolve?

Solve in w^2 instead of w - then there shouldn't be imaginary parts in the solution: F = @(w) ((1-p)/C)*(kappa^q - (w^2)^q)+y+z...

Is this a correct way to use fsolve?

Solve in w^2 instead of w - then there shouldn't be imaginary parts in the solution: F = @(w) ((1-p)/C)*(kappa^q - (w^2)^q)+y+z...

circa un mese fa | 1

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