MATLAB: How to convert y=f(x) to x=f(y)

Question

I want to express s in terms of x

syms s;

a=1;

b=1.6;

x=(b+a)/2+(b-a)/2*s;

x=subs(x)

s=solve(x,s)

Answer 1

Try this:

syms s x 
a=1;
b=1.6;
Eq = x == (b+a)/2+(b-a)/2*s;
s=solve(Eq,s)

producing:

s =
(10*x)/3 - 13/3

Without the numeric substitutions:

syms a b s x 
Eq = x == (b+a)/2+(b-a)/2*s;
s=solve(Eq,s)

produces:

s =
(a + b - 2*x)/(a - b)

.