Warning: Error updating FunctionSurface. The following error was reported evaluating the function in FunctionLine update: Unable to convert expression into double array.

I'm trying to plot solution to the 2D unsteady state heat conduction equation, but when I try to plot the it I get an error. Please help, here is the code.

syms n x y Ta Tb T

H = 0.4;

L = 0.3;

Ta = symsum(80*((1-(-1)^n)/(n*pi))*sinh(n*pi*(0.4-y)/0.3)*sin(n*pi*x/0.3)/sinh(n*pi*0.4/0.3),n,1,Inf);

Tb = symsum(20*((1-(-1)^n)/(n*pi))*sinh(n*pi*y/0.3)*sin(n*pi*x/0.3)/sinh(n*pi*0.4/0.3),n,1,Inf);

T = Ta+Tb;

fsurf(Ta, [0 0.3 0 0.4]);

Error: Warning: Error updating FunctionSurface.

The following error was reported evaluating the function in FunctionLine update: Unable to convert expression

into double array.

function looks something like this:

Thanks

Answer 1

[VBBV]

%f true
  Ta = symsum(80*((1-(-1).^n)./(n*pi)).*sinh(n*pi*(0.4-y)./0.3).*sin(n*pi*x/0.3)./sinh(n*pi*0.4/0.3),n,1,Inf);
Tb = symsum(20*((1-(-1).^n)./(n*pi)).*sinh(n*pi*y/0.3).*sin(n*pi*x/0.3)./sinh(n*pi*0.4/0.3),n,1,Inf);

Try using element wise operator

[Hritik Chaudhary]

Sorry , still does not work :( .

[VBBV]

syms n x y Ta Tb T
H = 0.4;
L = 0.3;
Ta(x,y) = symsum(80*((1-(-1)^n)./(n*pi)).*sinh(n*pi*(0.4-y)/0.3).*sin(n*pi*x/0.3)./sinh(n*pi*0.4/0.3),n,1,Inf);
Tb(x,y) = symsum(20*((1-(-1)^n)./(n*pi)).*sinh(n*pi*y/0.3).*sin(n*pi*x/0.3)./sinh(n*pi*0.4/0.3),n,1,Inf);

T = Ta+Tb;
fsurf(T, [0 10 0 10]);

Try above with right values for x, y and H, L

[Hritik Chaudhary]

It works only for finite number of terms in summation.