The residual expression of a constraint, i.e. the amount by which it is violated, and the value of that violation. For instance, if our constraint is \(g(x) \leq 0\), the residual is \(max(g(x), 0)\) applied elementwise.

```
residual(object)
violation(object)
```

- object
A Constraint object.

A Expression representing the residual, or the value of this expression.