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Extract Categorical Map Attributes


This functor extracts the attributes and calculates basic statistics from a map and as a result creates a table that contains the extracted attributes.


Name Type Description
Map Map Map whose attributes will be extracted.
Categorical Map Categorical Map Map whose classes will be used to break the input map into subregions.

Optional Inputs

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


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



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

The functor employs a lookup table with keys to the attributes. Each key 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 lookup 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.

Basic Attributes

Key Predefined Name Description
1 “lines” number of lines
2 “columns” number of columns
3 “cells” number of cells (number of lines multiplied by the number of columns)
4 “layers” number of layers
5 “cellHeight” cell height (in meters)
6 “cellWidth” cell width (in meters)
7 “cellArea” cell area (in hectares)
19 “cellType” cell type code
20 “nullValue” null value

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)

Cell Type Codes

The codes used to represent all the possible cells types, corresponding to attribute key 19 (“cellType”), are listed below. It is possible to convert the corresponding code back into a Cell Type.

Key Cell Type
0 Unsigned 1 Bit Integer
1 Signed 8 Bit Integer
2 Unsigned 8 Bit Integer
3 Signed 16 Bit Integer
4 Unsigned 16 Bit Integer
5 Signed 32 Bit Integer
6 Unsigned 32 Bit Integer
7 IEEE 754 32 Bit Real

Layer Attributes

The layer attributes1) are returned in a second table. This table has the following format.

Column Name Key or Data? Column Type Description
“Layer_Index” Key Real The index of the corresponding layer
“Layer_Name” Key String The name of the corresponding layer

Internal Name


Currently, only the layer name is the only layer specific attribute returned.