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Extract Map Attributes

Description

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

Inputs

Name Type Description
Map Map Map whose attributes will be extracted.

Optional Inputs

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

Outputs

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

Group

Notes

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 code1)
20 “nullValue” null value2)

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:

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

Internal Name

ExtractMapAttributes

1) , 2)
Dinamica EGO 2.0 and above