how do i use contour command for rectangular plate ?
4 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
mehmet salihi
le 1 Juin 2021
Commenté : mehmet salihi
le 2 Juin 2021
dear friends,
i have one regtangular plate and when i use contour command i did not obtain the figure i want, could you please see where do i have mistake.
i am sharing also the figure i want to obtain
%%% Point Gauss Seidel (PGS)
close all, clc
format short g
%Defining the constants
L=1; % length
H=2; % Height
deltax=0.05
deltay=0.05
Beta=deltax/deltay
Beta2=Beta^2
jn=H/deltay % Maximum number of grid points along y
im=L/deltax % Maximum number of grid points along x
T1=100; T2=0; T3=0; T4=0; % boundary conditions
y=2:-deltay:0;
x=0:deltax:L;
% initialize T_old to the initial guess values
T_old=zeros(jn+1,im+1);
% set boundary conditions
T_old(1,1:im+1)=T1;
T_old(jn+1,1:im+1)=T3;
T_old(2:jn+1,1)=T2;
T_old(2:jn+1,im+1)=T4;
T_new = T_old;
Error = 0.011; % could be any number that is greater than Errormax
Errormax=0.01;
t=0;
while Error > Errormax
t=t+1;
for i=2:jn
for j=2:im
T_new(i,j)=(1/(2*(1+Beta2)))* (T_new(i-1,j)+T_new(i+1,j)+Beta2*(T_new(i,j+1)+T_new(i,j-1)) ) ;
end
end
Error = sum(sum(abs(T_old-T_new),2)) ;
T_old = T_new;
end
contour(T_new(2:en,:))
0 commentaires
Réponse acceptée
Cris LaPierre
le 1 Juin 2021
Modifié(e) : Cris LaPierre
le 1 Juin 2021
Include your x and y vectors when plotting. You'll have to do some manipulation of y since you create it starting at 2 and decrement to 0. You can also specify the number of contour levels if you want that to match.
You'll also want to format the axes so they use the same spacing (axis equal)
%Defining the constants
L=1; % length
H=2; % Height
deltax=0.05;
deltay=0.05;
Beta=deltax/deltay;
Beta2=Beta^2;
jn=H/deltay; % Maximum number of grid points along y
im=L/deltax; % Maximum number of grid points along x
T1=100; T2=0; T3=0; T4=0; % boundary conditions
y=2:-deltay:0;
x=0:deltax:L;
% initialize T_old to the initial guess values
T_old=zeros(jn+1,im+1);
% set boundary conditions
T_old(1,1:im+1)=T1;
T_old(jn+1,1:im+1)=T3;
T_old(2:jn+1,1)=T2;
T_old(2:jn+1,im+1)=T4;
T_new = T_old;
Error = 0.011; % could be any number that is greater than Errormax
Errormax=0.01;
t=0;
while Error > Errormax
t=t+1;
for i=2:jn
for j=2:im
T_new(i,j)=(1/(2*(1+Beta2)))* (T_new(i-1,j)+T_new(i+1,j)+Beta2*(T_new(i,j+1)+T_new(i,j-1)) ) ;
end
end
Error = sum(sum(abs(T_old-T_new),2)) ;
T_old = T_new;
end
%% create contour plot
contour(x,fliplr(y),T_new,17,'k')
xlabel('X')
ylabel('Y')
axis equal
3 commentaires
Cris LaPierre
le 2 Juin 2021
Levels is an optional input. When you do not specify the levels, the contour function chooses the levels automatically.
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Calculus dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!