GEO 151 Study Guide - Midterm Guide: Analytic Geometry, Cartesian Coordinate System, Institute For Operations Research And The Management Sciences

• School: Ryerson University
• Department: Geography
• Course: GEO 151
• Professor: Steven Swales

Document Summary

Geographical phenomena can be represented in two dimensions by main entity types- point, lines and areas. Example: points can represent hotels, lines can represent ski lifts and areas can represent forests. Problems associated with simplifying the complexities of the real world into entity types include the dynamic nature of the real world, the identification of discrete and continuous features, and the scale at which a particular problem needs addressing. The dynamic nature of the world poses two problems for the entity- definition phase of the project. 1) how to select the entity type that provides the most appropriate representation for the feature being modelled: the second problem is how to represent changes over time. The definition of entity types is also hampered by the fact that many real world features simply do not fit into the categories of entities available. Turning special entities into graphical representation is the second stage in designing and implementing a data model.