GIS is a system designed to capture store manipulate analyze manage and present all types of geographical data Wikipedia maps data tools computers Geography is visualized in maps wwwarcgiscom ID: 1002502
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1. What is GISA geographic information system (GIS) is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographical data. -- Wikipediamapsdatatoolscomputers
2. Geography is visualized in mapswww.arcgis.commap
3. Maps are built from data mapdataRoadName: E. Dean Keeton StType: Div HighwaySpeed: 35 mphShape: [Geometry]BuildingName: Ernest Cockrell Jr HallAddress: 301 E. Dean Keeton StShape: [Geometry]Shape includes the geometry of the feature and where it is located on earth
4. Vector data represent discrete featuresmapdatapolygonslinespoints
5. Raster data form a grid of cells or pixelsmapdata
6. More Raster Examplesmapdatarainfallelevationland use
7. There are many more data typesmapdatatriangulated irregular networkmultipatchannotationMartin Luther King Dr W
8. TIN on Dean Keaton StRLMCPE
9. TIN Points on Dean Keaton546.911547.2547.23546.91
10. Connected Map, Chart and AnimationTropical Storm Fernandhttp://www.msnbc.msn.com/id/26295161/ns/weather/
11. Geographic Data ModelConceptual Model – a set of concepts that describe a subject and allow reasoning about itMathematical Model – a conceptual model expressed in symbols and equationsData Model – a conceptual model expressed in a data structure (e.g. ascii files, Excel tables, …..)Geographic Data Model – a conceptual model for describing and reasoning about the world expressed in a GIS database
12. Data Model based on a collection of data themes
13. Spatial Data: Vector formatPoint - a pair of x and y coordinates(x1,y1)Line - a sequence of pointsPolygon - a closed set of linesNodevertexVector data are defined spatially:
14. Kissimmee watershed, FloridaThemes
15. Attributes of a Selected Feature
16. Raster and Vector DataPointLinePolygonVectorRasterRaster data are described by a cell grid, one value per cellZone of cells
17. http://srtm.usgs.gov/srtmimagegallery/index.htmlSanta Barbara, California
18. Origin of Geographic Coordinates(0,0)EquatorPrime Meridian
19. Latitude and LongitudeLongitude line (Meridian)NSWERange: 180ºW - 0º - 180ºELatitude line (Parallel)NSWERange: 90ºS - 0º - 90ºN(0ºN, 0ºE) Equator, Prime Meridian
20. Latitude and Longitude in North America90 W120 W60 W30 N0 N60 NAustin: Logan:(30°18' 22" N, 97°45' 3" W)(41°44' 24" N, 111°50' 9" W)
21. Map ProjectionCurved EarthGeographic coordinates: f, l(Latitude & Longitude)Flat Map Cartesian coordinates: x,y(Easting & Northing)
22. Earth to Globe to MapRepresentative FractionGlobe distanceEarth distance =Map Scale:Map Projection:Scale FactorMap distanceGlobe distance =(e.g. 1:24,000)(e.g. 0.9996)
23. Coordinate Systems(fo,lo)(xo,yo)XYOriginA planar coordinate system is defined by a pairof orthogonal (x,y) axes drawn through an originGeographic CoordinatesProjected Coordinates