ClassifyUniqueValues

Classify functions ClassifyUniqueValues

syntax

• ClassifyUniqueValues(a, domain unit)

definition

ClassifyUniqueValues(a, domain unit) results in a data item with class breaks, based on the unique values occurring in the data item a. The resulting values unit is the values unit of data 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 ClassifyUniqueValues function results in a number of class breaks, based on the number of rows of the domain unit argument. If the data item to be classified contains more unique values than this number, the resulting set is cut off at this number. If the data item to be classified contains fewer unique values, the resulting data item is completed by repeating the highest unique value.

To create a new domain unit with all unique values occurring in the original data set once, use the unique function.

This unique function works similarly to the unique values function in the GUI, which can be applied by requesting the Palette Editor of a map layer and activating the Classify > Unique values classification.

applies to

• data item a with Numeric value type
• domain unit with value type from group CanBeDomainUnit

since version

7.019

example

attribute<nrPersons> classifyUvNrInh (inh_4K) := ClassifyUniqueValues(NrInh, inh_4K);

classifyUvNrInh
0
2
20
55

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