Polat plot with colors depending on values.
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Hello,
I'm solving PDE system numerically, as a result I've got the matrix sized (size(r), size(theta)) with values of function in different polar coords (radius, angle). I need to plot the surface like on this picture

The color of point must depend on value from result matrix.
Is there any built-in solution for this task? Here is the main part of my code, if it helps.
for t=1:nt-1
for i=2:nr-1
for j=2:nth-1
%derivatives
d2udr2= (u(i+1,j,t)-2*u(i,j,t)+u(i-1,j,t))/hr^2;
d2udth2= (u(i,j+1,t)-2*u(i,j,t)+u(i,j-1,t))/hr^2;
dudr=(u(i+1,j,t)-u(i-1,j,t))/(2*hr);
d2vdr2= (v(i+1,j,t)-2*v(i,j,t)+v(i-1,j,t))/hr^2;
dvdr=(v(i+1,j,t)-v(i-1,j,t))/(2*hr);
d2vdth2= (v(i,j+1,t)-2*v(i,j,t)+v(i,j-1,t))/hr^2;
%centre nodes
u(i,j,t+1)=u(i,j,t)+ht*(psi*(d2udr2+(1/r(i))*dudr+d2udth2)+u(i,j,t)*(1-k*v(i,j,t)));%u(i,j,t)*(1-ro*b*v(i,j,t))*(1-b*v(i,j,t)-u(i,j,t))); %u(i,j,t)*(1-u(i,j,t)-c*v(i,j,t)));
v(i,j,t+1)=v(i,j,t)+ht*(mu*(d2vdr2+(1/r(i))*dvdr+d2vdth2)+a*v(i,j,t)*(1-x*u(i,j,t)));%a*v(i,j,t)*(1-q*u(i,j,t))*(1-u(i,j,t)-b*v(i,j,t)));%a*v(i,j,t)*(1-c*u(i,j,t)-b*v(i,j,t)));
end
end
%boundaries for r
for j=1:nth
u(1,j,t+1)=u(3,j,t+1);
u(nr,j,t+1)=u(nr-2,j,t+1);
v(1,j,t+1)=v(3,j,t+1);
v(nr,j,t+1)=v(nr-2,j,t+1);
end
u(:,1,t+1)=u(:,nth-1,t+1);
v(:,1,t+1)=v(:,nth-1,t+1);
u(:,nth,t+1)=u(:,2,t+1);
v(:,nth,t+1)=v(:,2,t+1);
% %corners
u(1,1,t+1)=u(1,2,t+1);
u(1,nth,t+1)=u(1,nth-1,t+1);
u(nr,1,t+1)=u(nr-1,1,t+1);
u(nr,nth,t+1)=u(nr-1,nth,t+1);
v(1,1,t+1)=v(1,2,t+1);
v(1,nth,t+1)=v(1,nth-1,t+1);
v(nr,1,t+1)=v(nr-1,1,t+1);
v(nr,nth,t+1)=v(nr-1,nth,t+1);
end
Answers (1)
Danila Zharenkov
on 11 Mar 2014
0 votes
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