Ode45 data keeps refreshing

Hello, I would appreciate if someone help me.

My problem is that I have 5 polyonimals and I made them switch when the value reaches umax it switch to the next one, but I want to stay there or move forwand to the next one polyonimal.

I did the following code, the problem is ode calls this function at each loop and u1max,u2max,u3max,u4max,u5max keeps getting refreshing.

function udot = ok3(t,u,p1,p2,p3,p4,p5,m,maxu,maxT,u1max,u2max,u3max,u4max,u5max)
syms z p(z)
T=symsum(p(m+1-z)*(u(1))^z,z,0,m);  

if u(1)<=u1max 
for y=1:m+1 
   T=subs(T,p(y),p1(y)); 
end
elseif u(1)<=u2max 
    u1max=5000;
for y=1:m+1 
   T=subs(T,p(y),p2(y));
end
elseif u(1)<=u3max 
    u1max=5000; u2max=5000;
for y=1:m+1 
   T=subs(T,p(y),p3(y));  
end
elseif u(1)<=u4max
    u1max=5000; u2max=5000; u3max=5000
for y=1:m+1 
   T=subs(T,p(y),p4(y));  
end
elseif u(1)<=u5max
    u1max=5000; u2max=5000; u3max=5000; u4max=5000;
for y=1:m+1 
   T=subs(T,p(y),p5(y)); 
end
else
    T=maxT;
    u(1)=maxu;
end
.
.
.
.
udot=double([SM1;SF]);

end

Answer 1

[darova]

Try persistent

function udot = ok3(t,u,P,m,maxu,maxT,umax)
syms z p(z)
T=symsum(p(m+1-z)*(u(1))^z,z,0,m);  
persistent umaxc
if isempty(umaxc)
    umaxc = u(1);
end
umaxc = max(u(1),umaxc);

if any(umaxc <= umax)
    k = find(umaxc<=umax,1,'first');
    pp = P{k};
    %code
else 
    T=maxT;
    u(1)=maxu;
end
end

Your main script

clear function          % clear persistent variable
P = {p1 p2 p3 p4 p5};
umax = [u1max u2max u3max u4max u5max];