I’m trying to solve an boundary value problem with eigenvalues, following the article ( https://doi.org/10.1063/5.0155331 )

where and At are certain numbers and Q() is a known function, erf function in this case.
is the unknown function and the eigenvalue.
The boundary condition is , so I specified
For small alphas my code with bvp5c works well.
However for large alphas, my solution deviates from the result in the article, and I’m encountering messages like
Warning: Results may be inaccurate because of an ill-conditioned Jacobian whose reciprocal condition number is 2.03573e-39
I guess the boundary values may be too small and tried to scale my boundary values with C*exp(-3/alpha) but the problem remains.

How can I solve the problem? Fig.1 in https://doi.org/10.1063/5.0155331 can be referred as a correct solution to this problem. My solution looks similar to it but deviates in asymptotic values.
eigenvalues0999 = zeros(1, 30);

global alpha;
global At;
options = bvpset(‘RelTol’,1e-5,’AbsTol’,1e-5);

At = 0.999;
for i=1:30
alpha=1/i;
Psi1 = 1;
solinit = bvpinit(linspace(-3,6,30000),@mat4init,Psi1);
sol = bvp5c(@mat4ode, @mat4bc, solinit,options);
eigenvalues0999(1,i) = sol.parameters;
end

figure(Color="white");
plot(eigenvalues0999);
grid on;
legend(‘0′,’0.243′,’0.5′,’0.843′,’0.999′,’FontSize’, 14)
xlabel(‘alpha^{-1}’,’FontSize’, 14);
ylabel(‘Psi’,’FontSize’, 14);
set(gca, ‘FontSize’, 14);

function dydx = mat4ode(x,y,Psi1) % equation being solved
global alpha;
global At;
dydx = [y(2)
(-alpha^2*At*2/sqrt(pi)*exp(-x.^2)*y(2)+(1+At*erf(x)-alpha*Psi1*2/sqrt(pi)*exp(-x.^2))*y(1))/(alpha^2*(1+At*erf(x)))];
end

function res = mat4bc(ya,yb,Psi1) % boundary conditions
global alpha;
res = [ya(2)-1/alpha*exp(-3/alpha)
abs(yb(1))+abs(yb(2))
%yb(2)
ya(1)-exp(-3/alpha)];
end

function yinit = mat4init(x) % initial guess function
global alpha;
yinit = [exp(-abs(x)/alpha)
-sign(x)*1/alpha*exp(-abs(x)/alpha)];
endI’m trying to solve an boundary value problem with eigenvalues, following the article ( https://doi.org/10.1063/5.0155331 )

where and At are certain numbers and Q() is a known function, erf function in this case.
is the unknown function and the eigenvalue.
The boundary condition is , so I specified
For small alphas my code with bvp5c works well.
However for large alphas, my solution deviates from the result in the article, and I’m encountering messages like
Warning: Results may be inaccurate because of an ill-conditioned Jacobian whose reciprocal condition number is 2.03573e-39
I guess the boundary values may be too small and tried to scale my boundary values with C*exp(-3/alpha) but the problem remains.

How can I solve the problem? Fig.1 in https://doi.org/10.1063/5.0155331 can be referred as a correct solution to this problem. My solution looks similar to it but deviates in asymptotic values.
eigenvalues0999 = zeros(1, 30);

global alpha;
global At;
options = bvpset(‘RelTol’,1e-5,’AbsTol’,1e-5);

At = 0.999;
for i=1:30
alpha=1/i;
Psi1 = 1;
solinit = bvpinit(linspace(-3,6,30000),@mat4init,Psi1);
sol = bvp5c(@mat4ode, @mat4bc, solinit,options);
eigenvalues0999(1,i) = sol.parameters;
end

figure(Color="white");
plot(eigenvalues0999);
grid on;
legend(‘0′,’0.243′,’0.5′,’0.843′,’0.999′,’FontSize’, 14)
xlabel(‘alpha^{-1}’,’FontSize’, 14);
ylabel(‘Psi’,’FontSize’, 14);
set(gca, ‘FontSize’, 14);

function dydx = mat4ode(x,y,Psi1) % equation being solved
global alpha;
global At;
dydx = [y(2)
(-alpha^2*At*2/sqrt(pi)*exp(-x.^2)*y(2)+(1+At*erf(x)-alpha*Psi1*2/sqrt(pi)*exp(-x.^2))*y(1))/(alpha^2*(1+At*erf(x)))];
end

function res = mat4bc(ya,yb,Psi1) % boundary conditions
global alpha;
res = [ya(2)-1/alpha*exp(-3/alpha)
abs(yb(1))+abs(yb(2))
%yb(2)
ya(1)-exp(-3/alpha)];
end

function yinit = mat4init(x) % initial guess function
global alpha;
yinit = [exp(-abs(x)/alpha)
-sign(x)*1/alpha*exp(-abs(x)/alpha)];
end I’m trying to solve an boundary value problem with eigenvalues, following the article ( https://doi.org/10.1063/5.0155331 )

where and At are certain numbers and Q() is a known function, erf function in this case.
is the unknown function and the eigenvalue.
The boundary condition is , so I specified
For small alphas my code with bvp5c works well.
However for large alphas, my solution deviates from the result in the article, and I’m encountering messages like
Warning: Results may be inaccurate because of an ill-conditioned Jacobian whose reciprocal condition number is 2.03573e-39
I guess the boundary values may be too small and tried to scale my boundary values with C*exp(-3/alpha) but the problem remains.

How can I solve the problem? Fig.1 in https://doi.org/10.1063/5.0155331 can be referred as a correct solution to this problem. My solution looks similar to it but deviates in asymptotic values.
eigenvalues0999 = zeros(1, 30);

global alpha;
global At;
options = bvpset(‘RelTol’,1e-5,’AbsTol’,1e-5);

At = 0.999;
for i=1:30
alpha=1/i;
Psi1 = 1;
solinit = bvpinit(linspace(-3,6,30000),@mat4init,Psi1);
sol = bvp5c(@mat4ode, @mat4bc, solinit,options);
eigenvalues0999(1,i) = sol.parameters;
end

figure(Color="white");
plot(eigenvalues0999);
grid on;
legend(‘0′,’0.243′,’0.5′,’0.843′,’0.999′,’FontSize’, 14)
xlabel(‘alpha^{-1}’,’FontSize’, 14);
ylabel(‘Psi’,’FontSize’, 14);
set(gca, ‘FontSize’, 14);

function dydx = mat4ode(x,y,Psi1) % equation being solved
global alpha;
global At;
dydx = [y(2)
(-alpha^2*At*2/sqrt(pi)*exp(-x.^2)*y(2)+(1+At*erf(x)-alpha*Psi1*2/sqrt(pi)*exp(-x.^2))*y(1))/(alpha^2*(1+At*erf(x)))];
end

function res = mat4bc(ya,yb,Psi1) % boundary conditions
global alpha;
res = [ya(2)-1/alpha*exp(-3/alpha)
abs(yb(1))+abs(yb(2))
%yb(2)
ya(1)-exp(-3/alpha)];
end

function yinit = mat4init(x) % initial guess function
global alpha;
yinit = [exp(-abs(x)/alpha)
-sign(x)*1/alpha*exp(-abs(x)/alpha)];
end bvp5c, solve MATLAB Answers — New Questions

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Modify the Task 2 & 7 section of the script so that it performs the red shift calculation on the second star in spectra, not the sixth.
I have changed s to the second column (s= spectra(:,2)), and that is right.
How do I get the correct values of lambdaHa and speed?Modify the Task 2 & 7 section of the script so that it performs the red shift calculation on the second star in spectra, not the sixth.
I have changed s to the second column (s= spectra(:,2)), and that is right.
How do I get the correct values of lambdaHa and speed? Modify the Task 2 & 7 section of the script so that it performs the red shift calculation on the second star in spectra, not the sixth.
I have changed s to the second column (s= spectra(:,2)), and that is right.
How do I get the correct values of lambdaHa and speed? onramp, stellar motion 14.1, inramp, stellar motion MATLAB Answers — New Questions

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Hello all,
hopefully a very simple question, with a simple solution:
I would like to import some GeoTIFFs to build my 3D model based on.
But after the import the image looks slightly rotated and no longer parallel to the X and Y axes.

Can someone expain me why?
When I import the same GeoTIFF with the mapping toolbox the result looks like expected:

I assume it has something to do with projection or World Origin. But I can’t identify it.

Thx in advance,
TimHello all,
hopefully a very simple question, with a simple solution:
I would like to import some GeoTIFFs to build my 3D model based on.
But after the import the image looks slightly rotated and no longer parallel to the X and Y axes.

Can someone expain me why?
When I import the same GeoTIFF with the mapping toolbox the result looks like expected:

I assume it has something to do with projection or World Origin. But I can’t identify it.

Thx in advance,
Tim Hello all,
hopefully a very simple question, with a simple solution:
I would like to import some GeoTIFFs to build my 3D model based on.
But after the import the image looks slightly rotated and no longer parallel to the X and Y axes.

Can someone expain me why?
When I import the same GeoTIFF with the mapping toolbox the result looks like expected:

I assume it has something to do with projection or World Origin. But I can’t identify it.

Thx in advance,
Tim geotiff, data import, gis MATLAB Answers — New Questions

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I set the input for the prismatic joint to ‘provided by input’ in the motion settings, and while I found that the input should include information on position, velocity, and acceleration, I couldn’t find the exact format in which this information should be provided. Could you please let me know the required format?I set the input for the prismatic joint to ‘provided by input’ in the motion settings, and while I found that the input should include information on position, velocity, and acceleration, I couldn’t find the exact format in which this information should be provided. Could you please let me know the required format? I set the input for the prismatic joint to ‘provided by input’ in the motion settings, and while I found that the input should include information on position, velocity, and acceleration, I couldn’t find the exact format in which this information should be provided. Could you please let me know the required format? simulink, simscape MATLAB Answers — New Questions

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