v.kcv - Randomly partition points into test/train sets.
v.kcv [-dq] input=name output=name k=integer column=string
[--overwrite] [--verbose] [--quiet]
Allow output files to overwrite existing files
Verbose module output
Quiet module output
Name of input vector map
Name for output vector map
Number of partitions
Name for new column to which partition number is written
v.kcv randomly divides a points lists into k sets of test/train
data (for k-fold cross validation). Test partitions are mutually
exclusive. That is, a point will appear in only one test partition
and k-1 training partitions. The program generates a random point
using the selected random number generator and then finds the closest
point to it. This site is removed from the candidate list (meaning
that it will not be selected for any other test set) and saved in
the first test partition file. This is repeated until enough points
have been selected for the test partition. The number of points
chosen for test partitions depends upon the number of sites available
and the number of partitions chosen (this number is made as consistent
as possible while ensuring that all sites will be chosen for testing).
This process of filling up a test partition is done k times.
An ideal random sites generator will follow a Poisson dis only be as
random as the original points. This program simply divides points
up in a random manner.
Be warned that random number generation occurs over the intervals
defined by the region of the map.
This program may not work properly with Lat-long data.
v.random and g.region
James Darrell McCauley ,
when he was at: Agricultural Engineering Purdue University
Update to 5.7 Radim Blazek 10 / 2004
Last changed: $Date: 2011-11-08 01:42:51 -0800 (Tue, 08 Nov 2011) $
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