Hey guys i am currently attempting to do some modelling with maple, i need to solve a PDE system, i am using the following code and am confused with the error i'm getting. restart: M[Star]:=2*10^30: M[planet]:=2*10^27: q:=(M[planet])/(M[Star]): g:=sqrt((R-a)^(2)): H:=0.0333*R^(1): Delta[p]:=H: Alpha := unapply(piecewise(R <> a, 6.67*q^2*10^(-11)*M[Star]*(a/Delta[p])^4/(2*R), R = a, 1), R, a)

Hey i am trying to get maple to do some differential equation solving and i am running into some major road blocks.

the code i am using is as follows:

restart;

M[Star] := 2*10^30;

M[planet] := 2*10^27;

q := M[planet]/M[Star];

g := sqrt((R-a)^2);

H := 0.333e-1*R;

Delta[p] := H;

Hey, i am a undergraduate at uni and i have run in to a bit of a roadblock with Maple.

I am using the following code;

M[Star]:=2*10^(30);

M[planet]:=2*10^(27);

q:=(M[planet])/(M[Star]);

Delta[p]:=max(H,|R-a|);

Alpha(R,a):=piecewise(R<a, -(q^(2)*6.67*10^(-11)*M[Star])/(2*R)*(R/(Delta[p]))^(4) ,R>a,(q^(2)*6.67*10^(-11)*M[Star])/(2*R)*((a)/(Delta[p]))^(4) );

PDE1:=diff(S(R,t),t)=(3/(R))*(diff(R^(1/(2))*(diff( S(R,t)*R^(1/(2))-(2*Alpha(R,a)*S(R,t)^(3/(2)))/((6.67*10^(-11)*M[Star])^(1/(2))),R)),R));