Table of Contents

Categorization Type

A categorization is a set of categories (classes) used to label the cells of a Categorical Map — each category defined by a value, a name, and a display color.

GUI Editor

Graphical representation of the categorization editor

EGO Script

A constant representing a set of categories is written in EGO Script using the following syntax: 

[
  1, "Rondonia", (139, 35, 35),
  2, "Acre", (105, 211, 169),
  3, "Amazonas", (149, 149, 238),
  4, "Roraima", (177, 177, 66),
  5, "Para", (238, 203, 149),
  6, "Amapa", (62, 12, 96),
  7, "Tocantins", (238, 149, 149),
  8, "Maranhao", (51, 255, 204),
  9, "Mato_Grosso", (211, 105, 211)
]

Each line describes one category through three elements: its value, name, and color.

  • Value — a signed 32-bit integer corresponding to a cell value in a categorical map, in the range -2,147,483,648 to 2,147,483,647. Ex: -10, 1, 200.
  • Name — a non-empty string enclosed in double quotes. It must start with a letter, followed by letters, numbers, and underscores (_). Ex: “forest”, “deforestation”, “class_1”.
  • Color — a three-element tuple enclosed in parentheses, using the (R, G, B) notation: red, green, and blue components, in that order. Each component must be in the range [0, 255]. Ex: (255, 0, 0), (128, 128, 128). (0, 0, 0) is black and (255, 255, 255) is white.

Commas between elements are optional. Categories do not need to be contiguous.

Note: Because a category value is a signed 32-bit integer, a categorization cannot be attached to a map whose cell type is Unsigned 32-bit Integer or Float 32-bit — neither type can represent the full range and precision of a signed 32-bit integer.
Note: A categorization accepts at most 20,000,000 categories; defining more raises an error. This default is used in most situations and is rarely a practical limit.

Automatic Conversions

  • Converted from: Table Type, Categorical Map — a Categorical Map converts directly to its Categorization, extracting the value/name/color definitions already attached to the map; this is a separate, one-way path from the Table Type conversion below and does not pass through a Table.

The Table Type conversion works in both directions — from a Table into a Categorization, and from a Categorization into a Table. In either direction, the table must have the following columns, in order:

Column Type Description
Category value *#real (key) The category value.
Category name #string The category name. If left blank when converting into a Categorization, the category is automatically named using the pattern class_N — or class_nN if the value is negative, where N is the absolute value — the same fallback used for any category left unnamed.
Category red color #real The category's red color component, in the range [0, 255].
Category green color #real The category's green color component, in the range [0, 255].
Category blue color #real The category's blue color component, in the range [0, 255].

The following CSV table represents the same categories shown in the EGO Script example above: 

Value*, Name, Color_Red, Color_Green, Color_Blue, 
1, Rondonia, 139, 35, 35,
2, Acre, 105, 211, 169,
3, Amazonas, 149, 149, 238,
4, Roraima, 177, 177, 66,
5, Para, 238, 203, 149,
6, Amapa, 62, 12, 96,
7, Tocantins, 238, 149, 149,
8, Maranhao, 51, 255, 204,
9, Mato_Grosso, 211, 105, 211

See Type System for the complete conversion reference across all types.