fix an incomplete difference matrix by guessing from differences between locations close to the ones whose values are missing


diffix -L [-o filename] difference-table-file location-file

diffix -a float [-o filename] difference-table-file location-file


Coordinates are in longitude/latitude
-a float
Coordinates are in x/y, with the given aspect ratio, (>= 1)
-o filename
Output file


Suppose you got a difference matrix, created by the program leven, that has a few missing values (NA's). Not all programs can handle a difference matrix with missing values, for example: mds, cluster. This program, diffix, makes reasonable guesses to fix an incomplete difference matrix.

Suppose there is no difference value available for locations A and B. This value is substituted by the average of the following 8 values:

Type of coordinates

To determine what locations are closest to the ones involved in missing differences, it must me determined how the coordinates must be interpreted.

Use option -L if the coordinates are given in longitude and latitude.

Use option -a if the coordinates are given in some user-defined rectangular grid, and specify the aspect ration between X- and Y-coordinates. This must be a value of 1.0 or greater, meaning a distance of 1X can represent a smaller geographical distance than a distance of 1Y.

Output file

The output file is a new difference matrix.