Object
Formally, an object-based data model is defined as: A data model that uses objects to organize data and stores spatial data and attribute data in a single system. [1] The object-based data model treats spatial data as objects instead of words. The ability to use a single system to store both spatial and attribute data is considered a major breakthrough by GIS software developers.
In GIS, an object can represent a spatial feature such as a road, a timber stand, or a hydrologic unit,[2] and almost anything that we work with in GIS can be represented as an object. For example, object oriented data models allow us to assign a timber stand properties of shape and extent so we can view the stand as a polygon, point or line in a GIS. [3] Just like we use a pointer arrow controlled by a mouse or touch pad when navigating the cursor on our computer, when data is displayed in object form, the information is normally displayed in menus, icons, and dialog boxes instead of a command line.
A core object-oriented data model consists of a number of concepts: 1) Object and object identifier: Any real thing can be modeled as an object. 2) Attributes and methods: Every object has a state and a behavior. 3) Class: A means of grouping all the objects that have the same set of attributes and methods. Without classes, object management in a GIS would be almost impossible.[4]
Sources
- ↑ Chang, Kang-Sung. Introduction to Geographic Information Systems (2008). 4th Edition. p14
- ↑ Chang, Kang-Sung. Introduction to Geographic Information Systems (2008). 4th Edition. p62
- ↑ Chang, Kang-Sung. Introduction to Geographic Information Systems (2008). 4th Edition. p62
- ↑ http://www.cs.sfu.ca/CC/354/zaiane/material/notes/Chapter8/node3.html
| Authors | Tyson Barlow |
|---|---|
| Editors | Dantley |
| BoK Topics | DM2-3 |
| 311 Weeks | 2 |
| Tags | description, terms |
