GEOG
4/575 Lab 3. Data File and Geodatabase
Structures
Due Oct 22 before class.
Descriptions:
This lab allows you
to explore different ArcGIS/ArcInfo
data layers and their file structures. You will also learn to use personal (or file-based)
Geodatabase to manage GIS data layers and access
various online GIS data sources. Please read the directions below carefully.
They provide the updates to the instructions on the textbook.
Directions:
Finish all tasks in Chang’s Chapters 3 and 5 and submit answers to the questions at the end of this exercise. Lab exercise data are available in: I:\Students\Instructors\Geoffrey_Duh\GEOG4575\Chang_5e\chap3 and chap5 (or on the textbook CD). Please copy all these folders to your working directory in c:\users before you start.
Questions:
1. Illustrate the differences in data file structure between a coverage, a geodatabase feature class, and a shapefile. (Hint: Use Windows Explorer to view the data layers you used in this exercise and see how they differ from each other.
2. Can you import a feature class into a feature dataset that has a different map projection? Are feature classes in a feature dataset allowed to have different projections? Based on these answers, describe what would you do when importing two feature classes that have different projection into a feature dataset.
3. You have a polygon shapefile (e.g., census block) containing only population information (i.e., without area data of the polygons). Describe the steps to calculate the population density in each polygon.
4. What is the difference between a route and a regular polyline (or an arc) in ArcGIS? Can a route represent a path that is not physically connected from the beginning to the end? Give an example of what such routes might be.
5. Imagine that you have acquired a missing notebook
from the Lewis and Clark expedition that has the latitudes and longitudes of
all of the camas wetlands they encountered along the