diffekv.m
function xprim=diffekv(t,x)
xprim=zeros(3,1);
xprim(1)=x(3);
xprim(2)=x(1)+1;
xprim(3)=x(2)*exp(-x(3));
pde1.m
s=[0:0.1:1];
tspan=[0:0.1:1];
x=zeros(length(tspan),length(s));
y=x;z=x; %initierar x, y och z
for k=1:length(s)
[t,X]=ode45('diffekv',tspan,[s(k),s(k)^2,0]);
x(:,k)=X(:,1);
y(:,k)=X(:,2);
z(:,k)=X(:,3);
end
mesh(x,y,z) %pröva också meshz(x,y,z)