public enum BoundsType| Unbounded | 0 | Unbounded; i.e., between negative infinity and positive infinity. |
| BetweenZeroAndOne | 1 | Between 0 and 1, inclusive. |
| Nonnegative | 2 | Nonnegative; i.e., >= 0. |
| Nonpositive | 3 | Nonpositive; i.e., <= 0. |
| Custom | 4 | Custom bounds. |