Matlab error "Matrix dimensions must agree"
2 views (last 30 days)
Show older comments
Andrés Olvera
on 28 May 2020
Answered: Clemens Dierks
on 5 Nov 2020
I'm trying to get the integral() of a two functions but I keep getting this error and I don't know why
This is the code for the functions:
R = 0.5; %m
I = 2; %A
u0 = 4*pi*10^-7;
BiotSavart = (u0*R*I)/(4*pi);
max = 50;
px = -R:R/max:R;
py = -R:R/max:R;
pz = 0:R/max:2*R;
fy = @(t) sin(t)./((px-R*cos(t)).^2+(py-R*sin(t)).^2+pz.^2).^(3/2);
fz = @(t) (R-py.*sin(t)-px.*cos(t))./((px-R*cos(t)).^2+(py-R*sin(t)).^2+pz.^2).^(3/2);
By = pz * BiotSavart * integral(fy,0,2*pi);
Bz = BiotSavart * integral(fz,0,2*pi);
I get the error in this line:
fy = @(t) sin(t)./((px-R*cos(t)).^2+(py-R*sin(t)).^2+pz.^2).^(3/2);
0 Comments
Accepted Answer
Star Strider
on 28 May 2020
Integrating an array, set 'ArrayValued' to 'true':
By = pz .* BiotSavart .* integral(fy,0,2*pi, 'ArrayValued',1);
Bz = BiotSavart * integral(fz,0,2*pi, 'ArrayValued',1);
That runs without error.
2 Comments
More Answers (1)
Clemens Dierks
on 5 Nov 2020
Hello everybody,
I have the same error in a different situation.
I wrote the function to save two variables (matrices) in a xlsx file within two sheets.
Because xlswrite seems to be deprecated I used 'writematrix'.
A is 9000x2 matrix.
B is 1x1 vector.
The error occurs in when calling the method "writematrix".
Thank you in advance! :)
This is my code:
function [] = save_data(filename, A, B)
save(filename,'solution','DBC10');
writematrix(A, strcat(filename+'.xlsx'), 'sheet', 1)
writecell(B, strcat(filename+'.xlsx'),'sheet', 2)
end
0 Comments
See Also
Categories
Find more on Shifting and Sorting Matrices in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!