Table of Contents

Extract Categorical Map Attributes

Description

This functor calculates basic statistics from a map for each area delimited by a class. The result is returned in a table contains the extracted classes and their corresponding attributes.

Inputs

Name Type Description
Map Map Type Map whose attributes will be extracted.
Categorical Map Categorical Map Type Map whose classes will be used to delimit the calculation areas in the input.

Optional Inputs

Name Type Description Default Value
Extract Statistical Attributes Boolean Value Type If true, statistical attributes will be calculated. True

Outputs

Name Type Description
Attributes Table Type Table containing the attributes extracted from a map.

Group

Map Algebra

Notes

This functor analyzes all map layers. The resulting table refers to all of them.

The functor returns a table mapping classes and attributes to their corresponding attribute value. This table has the following format.

Column Name Key or Data? Column Type Description
“Attribute” Key Real The attribute key
“Category” Key Real The map category
“Value” Data Real The attribute from the map

Each “Attribute” has a predefined name. This name can be used to retrieve the corresponding attribute in Calculate Map, Calculate Categorical Map, Calculate Value and Calculate Lookup Table.

If it is not possible to determine any of these attributes, the corresponding entry in the output table is left blank. It determines the maximum and the minimum values only when there is at least one non null cell on the map for the given class.

Dynamic attributes

Key Predefined Name Description
8 “nullCells” number of null cells
9 “nonNullCells” number of non null cells
10 “minCell” minimum value (excluding null cells)
11 “maxCell” maximum value (excluding null cells)
12 “cellSum” sum of the values (excluding null cells)

Statistical attributes

Key Predefined Name Description
13 “meanCell” average (excluding null cells)
14 “cellVar” variance (excluding null cells)
15 “cellStd” standard deviation (excluding null cells)
16 “modeCell” mode (excluding null cells)
17 “medianCell” median (excluding null cells)
18 “uniqueCells” total unique occurrences (excluding null cells)

Internal Name

ExtractCategoricalMapAttributes