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## Manuals

### locmod

#### Description

derive a new set of coordinates from an old set of coordinates by merging or deleting items (locations)

#### Synopsis

locmod -L [-o filename] coordinate-file translation-file

locmod -a [-o filename] coordinate-file translation-file

#### Options

-L
  Coordinates are in longitude/latitude
-a
  Coordinates are in x/y
-o filename
  output file

#### Purpose

When you use difmod to derive a new difference matrix from an old one, you can use this program to derive the corresponding new coordinate file from the old coordinate file.

#### Type of coordinates

To determine the coordinates for a location that was formed by joining several old locations, the programs needs to know what type of coordinates are used.

Use option -L if the coordinates are given in longitude and latitude. New coordinates are calculated by determining the centre of gravity of points on the surface of a sphere.

Use option -a if the coordinates are given in some user-defined rectangular grid. New coordinates are calculated by averaging the old coordinates.