Slide 1:J426/J520/V550 Class 3
January 19, 2010
Slide 2:GIS layers
Map scale
Feature attributes
Slide 3:Multiple layers of geographic information displayed on single map
Geographic features
Points, lines, areas
Geographic surfaces
E.g., crime density surfaces
Images
Aerial photographs
Satellite images
Slide 6:Points
Using various symbols, colors, sizes
Lines
Using various line widths, patterns, colors
Areas
Using various colors, patterns
Slide 7:Points
Location of Business -SPEA building
Lines
Roads
Rivers
Areas
Indianapolis and other cities and towns
Parks
Geist Reservoir
Slide 8:Roads, rivers represented as areas
Slide 9:Indianapolis, other cities represented as points
Note different symbols for state capitals, other cities
Slide 10:Relationship of distances on map to distances in real world
Can be represented with scale showing real world distance on map
Can be represented with statement such as “one inch equals 10 miles”
In GIS, most generally represented as a fraction, relationship of distance on map to distance in real world
Slide 11:Various ways of indicating scale fractions
1 to 50,000
1 / 50,000
1 : 50,000
Means 1 inch on map represents 50,000 inches on ground
Slide 12:1 inch = 10 miles
1 : 633,600
Scale on map(based on printing out slide on 8 ½ x 11 paper)
Slide 13:Larger scale maps have larger scale fractions
Distance on map represents less distance on earth
Map covers smaller area
Smaller scale maps have smaller scale fractions
Distance on map represents greater distance on earth
Map covers larger area
Larger scale 1 : 9,000 Smaller scale 1 : 15,200,000 Slide 15:Geographic features (points, lines, areas) on map…
Linked to attribute information about those features in table
Allows identification of attributes for any feature
Allows use of attribute data in analysis