Error when using variable in axis

I've:

syms w we B U 

A = (w*U)/(sqrt((-w^2+we)^2+(B*w)^2));

syms R L C

Aw = subs(A,{B,we},{R/L,1/(L*C)});

fplot(subs(Aw,{U,R,L,C},{1,1,1,1}))

Amax = subs(Aw,{U,R,L,C,w},{1,1,1,1,1/sqrt(1*1)});

Actually that code above is not that of importance. The real problem occurs, when

axis([0 10 0 Amax])

is set. I can't really grasp why this gives an error. Amax just equals 1.

axis([0 10 0 1])

works nonetheless. Must be caused by subs probably

Answer 1

[Matt J]

Must be caused by subs probably

Yes, subs() does not give numeric output. You must convert it to numeric with double() or similar.

axis([1 1 1 double(Amax)])