Frequently asked question

How are values assigned to classes that are continuous and overlapping?

Last Published: April 25, 2020

Answer

Continuous overlapping classes are used for graduated legends based on floating point values. They are classification schemes in which the highest value of one class is used as the lowest value of the next class. If there is a feature in the theme that is equal to this value, the feature will be classified differently depending on the sort order of the classification.

Sorted ascending:

Class 1 = 1.1 - 1.2
Class 2 = 1.2 - 1.4
Class 3 = 1.4 - 1.6

If there is a feature with the value of 1.2, it will be placed in class 1. The first class uses all values greater than or equal to the lowest value, and less than or equal to the highest value. All subsequent classes use all values greater than the lowest value, and less than or equal to the highest value of the class. So in this classification, a feature with a value of 1.4 will be in class 2.

Sorted descending:

Class 1 = 1.4 - 1.6
Class 2 = 1.2 - 1.4
Class 3 = 1.1 - 1.2

If there is a feature with the value of 1.4, it will be placed in class 1. The first class uses all values greater than or equal to the lowest value, and less than or equal to the highest value. All subsequent classes use the values greater than or equal to the lowest value, and values less than the highest value. So in this classification, a feature with a value of 1.2 will be placed in class 2.

Article ID:000005744

Software:
  • Legacy Products

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