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syntax

definition

ClassifyJenksFisher(a, domain unit) results in a data item with class breaks, based on the Jenks Fisher classification method. The resulting values unit is the values unit of item a, the resulting domain unit is the domain unit argument.

  • a: numeric data item to be classified
  • domain unit: determining the number of class breaks.

description:

The Jenks Fisher classifcation method, also known as natural breaks, is implemented with a fast algorithm in the GeoDMS. For more information on this method and the algorithm used, see our Wiki.

The same function can also be applied from the GUI, by requesting the Palette Editor of a map layer and activate the Classify > JenksFisher classification (see also the User Guide). 

applies to

Data item a with Numeric value type

Domain unit with value type from group CanBeDomainUnit

since version

7.019

example

attribute<nrPersons> classifyJfNrInh (inh_4K)
:= ClassifyJenksFisher(NrInh, inh_4K);
classifyJfNrInh
0
300
750
1025
Table inh_4K, nr of rows = 4

NrInh
550
1025
300
200
0
null
300
2
20
55
860
1025
1025
100
750
Table District, nr of rows = 15

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