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## 1. Forward Computation

A *Forward Computation* is used to calculate a point's coordinates from distance and direction data from another set of coordinates:

Figure C-1 Forward Computation |
Equation C-1 |

Eqn (C-1) is a combination of the latitude and departure and coordinate equations from the **Traverse Computations** topic.

- North Lat is (+), South Lat is (–)
- East Dep is (+), West Dep is (–)

Dir_{AB} can be either a bearing or azimuth:

- If a bearing (0° to 90°) is used you must manually determine the correct algebraic sign for the Lat and Dep based on quadrant.
- Using azimuths (0° to 360°) automatically results in correct signs.

Because point B has two unknowns (N_{B} and E_{B}) it must be connected to point A with two measurments, distance and direction. Having only one or the other isn't sufficient to determine B's coordinates.