chebyball computes the largest possible ball inscribed in a polytope.

```
[xc,r] = chebyball(Constraint,options)
```

The typical use is as follows

```
sdpvar x y
Box = -1 <= [x y] <= 1;
[xc,r] = chebyball(Box);
plot(Box);
hold on
plot((x-xc(1)^2 + (y-xc(2))^2 <= r^2,[],'y')
```

The command solves a linear program, hence a linear programming solver must be available. If you want to control the selection of LP solver, you use the second options argument.