I have a space-dependent heat equation
Dc/dt = d/dx (D(x) dc/dx)
where the function D(x) is not defined as a function, but a position-dependent
vector of (n) points : diff
The vector diff has the same length of x, so I have x(i) and diff(i), i=1,…,n
How can I implement pdepe?

cb = pdepe(m,@heatcyl,@heatic,@heatbc,x,t); % run solver

function [c,f,s] = heatcyl(x,t,u,dudx) % diffusion equation equation
c = 1;
f = dudx*diff; ???? <<<<<<<<< not sure about that, since diff is a vector
s = 0;
end

function u0 = heatic(x) % initial condition
u0=1;
end

function [pl,ql,pr,qr] = heatbc(xl,ul,xr,ur,t) %BCs
global diff n
pl=0;
ql=1;
pr=ur;
qr=0;
end

Thank you!I have a space-dependent heat equation
Dc/dt = d/dx (D(x) dc/dx)
where the function D(x) is not defined as a function, but a position-dependent
vector of (n) points : diff
The vector diff has the same length of x, so I have x(i) and diff(i), i=1,…,n
How can I implement pdepe?

cb = pdepe(m,@heatcyl,@heatic,@heatbc,x,t); % run solver

function [c,f,s] = heatcyl(x,t,u,dudx) % diffusion equation equation
c = 1;
f = dudx*diff; ???? <<<<<<<<< not sure about that, since diff is a vector
s = 0;
end

function u0 = heatic(x) % initial condition
u0=1;
end

function [pl,ql,pr,qr] = heatbc(xl,ul,xr,ur,t) %BCs
global diff n
pl=0;
ql=1;
pr=ur;
qr=0;
end

Thank you! I have a space-dependent heat equation
Dc/dt = d/dx (D(x) dc/dx)
where the function D(x) is not defined as a function, but a position-dependent
vector of (n) points : diff
The vector diff has the same length of x, so I have x(i) and diff(i), i=1,…,n
How can I implement pdepe?

cb = pdepe(m,@heatcyl,@heatic,@heatbc,x,t); % run solver

function [c,f,s] = heatcyl(x,t,u,dudx) % diffusion equation equation
c = 1;
f = dudx*diff; ???? <<<<<<<<< not sure about that, since diff is a vector
s = 0;
end

function u0 = heatic(x) % initial condition
u0=1;
end

function [pl,ql,pr,qr] = heatbc(xl,ul,xr,ur,t) %BCs
global diff n
pl=0;
ql=1;
pr=ur;
qr=0;
end

Thank you! pdepe, pde space dependent diffusivity MATLAB Answers — New Questions

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