## CGAL::Level_interval<FaceHandle>

### Definition

The class Level_interval<FaceHandle> represents intervals for the minimum and maximum value of the z-coordinate of a face of a triangulation.

#include <CGAL/Level_interval.h>

### Requirements

The value_type of FaceHandle must be Face, which must have a nested type Vertex, which must have a nested type Point, whose Kernel_traits<Point>Kernel must have a nested type FT. These requirements are fulfilled, if one uses a CGAL triangulation and a CGAL kernel.

### Types

typedef FT | Value; | The type of the z-coordinate of points stored in vertices of faces.

### Creation

Level_interval<FaceHandle> i;
| Default constructor.
Level_interval<FaceHandle> i ( FaceHandle fh);
| Constructs the interval with smallest and largest z coordinate of the points stored in the vertices of the face fh points to.

### Operations

FaceHandle | i.face_handle () | returns the face handle.

### I/O

ostream& | ostream& os << i | Inserts the interval i into the stream os. Precondition: The output operator for *Face_handle is defined.

### Is Model for the Concept

Interval