As to why one uses pointers to pointers: 1  The name of an array usually yields the address of its first element. 2  Even though an array of strings sounds one-dimensional, it is in fact two-dimensional, since strings are character arrays. 3  A function f will need to accept an argument of type t ** if it is to alter a variable of type t *.
How to Use a Clinometer. A clinometer is used to measure angles. This is the method used by foresters to measure the height of a tree. The clinometer only works for measuring height when the observer is standing exactly one chain length away from the tree (66â or 100 links).
Girth is a measurement of the distance around the trunk of a tree measured perpendicular to the axis of the trunk. Use of girth to arrive at an equivalent diameter is an older forestry measurement that is still used. In the United States girth is measured at a height of 4.5 feet above ground level. Elsewhere in the world it is measured at a height of 1.3 meters, 1.4 meters, or 1.5 meters.