geographic information systems patty mcgray university of phoenix edtc 560 applications of...
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Geographic Information Systems
Patty McGrayUniversity of Phoenix
EDTC 560 Applications of Multimedia and Web Page Design
Janet WrightNovember 17, 2004
What is a GIS? An integration of five components
GIS functions
QueryQuery
AnalyzeAnalyze
StoreStore
DisplayDisplay
CaptureCapture
OutputOutput
Buildings
Streets
Reality
Customers
Capturing data
GISData
GPSGPS
480585.5, 3769234.6483194.1, 3768432.3485285.8, 3768391.2484327.4, 3768565.9483874.7, 3769823.0
480585.5, 3769234.6483194.1, 3768432.3485285.8, 3768391.2484327.4, 3768565.9483874.7, 3769823.0
CoordinatesCoordinates
Hardcopy mapsHardcopy mapsDigital dataDigital data
Storing vector data Real-world entities are abstracted into
three basic shapes
Points Points
Retail storesRetail stores
LinesLines
StreetsStreets
Areas/PolygonsAreas/Polygons
Land usesLand uses
Storing raster data Use square cells to model reality Each square holds a value
e.g. Photographs, TV
Reality(A highway)
X,Y
Rows
Columns
Query Identifying specific features
Identifying features based on conditions
Florida counties with a population greater than 300,000
Florida counties with a population greater than 300,000
AnalysisWhich parcels are within 50 feet of the road?
Which parcels are within 50 feet of the road?
Well type Drilled
Building owner Smith
Soil type Sandy
Well type Drilled
Building owner Smith
Soil type Sandy
ProximityProximity
OverlayOverlay
NetworkNetwork
Display
MapsMaps
GraphsGraphs
ReportsReports
Output
DocumentDocument
InternetInternetPaper mapPaper map
GIS Data
ImageImage
Organizing spatial data A GIS works with thematic layers of spatial
data
Answer questions by comparing different layers of data
Components of data Three general components to geographic
information
AttributesAttributesGeometryGeometry
Streets
BehaviorBehavior
Streets and highways may not intersect
Rules:Road nameRoad type
Using your data
The relative position of features determines relationships
I-80 connects San Francisco and New York
I-80 connects San Francisco and New York
San Francisco is contained by California
San Francisco is contained by California
I-80 has length and direction
I-80 has length and direction
New York is adjacent to the Atlantic Ocean
New York is adjacent to the Atlantic Ocean