The main focus of this presentation is on coordinate systems. We describe common problems that people have, key terms , how to apply coordinate systems in 10.1 and best practices.

1. Aligning data
Sabata Mcatshulwa

2. Presentation Outline
Common problems
Coordinate Systems
Geoprocessing Tools

3. Presentation Outline
Common problems
Coordinate Systems
Geoprocessing Tools

4. Common Problems

5. Common Problems

6. Common Problems

7. Demonstration

8. Presentation Outline
Common problems
Coordinate Systems
Geoprocessing Tools

9. Coordinate Systems
Geographic Coordinate Systems
• A measurement of a location on the Earth’s surface
expressed in degrees of latitude and longitude

10. Coordinate Systems
Geographic Coordinate Systems
• Three-dimensional spherical surface to define locations on the earth
• If two datasets are not referenced to the same geographic coordinate
system, you may need to perform a geographic (datum) transformation
• It is very important to correctly use a geographic transformation if it is
required.
• A GCS is often incorrectly called a datum, but a datum is only one part
of a GCS. A GCS includes an angular unit of measure, a prime
meridian, and a datum (based on a spheroid).
• The spheroid defines the size and shape of the earth model, while the
datum connects the spheroid to the earth's surface

11. Coordinate Systems
Projected Coordinate Systems
• A method by which the curved surface of the earth is
portrayed on a flat surface

12. Coordinate Systems
Projected Coordinate Systems
• Two-dimensional surface
• locations are identified by x,y coordinates on a grid, with the origin at
the center of the grid
• Unlike a GCS, a PCS has constant lengths, angles, and areas across
the two dimensions
• A PCS is always based on a GCS that is based on a sphere or
spheroid.

13. Coordinate Systems
Datums
• A frame of reference for measuring locations on the surface
of the Earth
• Cape (Port Elizabeth)
• Hartebeesthoek 1994 (Hartrao)
• WGS 1984 (Earth-centered = mass of the Earth)

14. TM
• Two degree zones (Transverse Mercator)
• LO = TM x, Cape
• WG = TM x, Hartebeesthoek

15. Coordinate Systems
• South Africa or a different area
• Create a .prj file
• Update the parameters

16. Demonstration

17. Presentation Outline
Common problems
Coordinate Systems
Geoprocessing Tools

18. Geoprocessing Tools
• Vector
• Define Projection = To assign a coordinate system
• Project = Change a coordinate system
• Raster
• Raster Properties = To assign a coordinate system
• Project Raster = Change a coordinate system

19. Geoprocessing Tools
− Spatial adjustment
• Projections - Shift data between coordinate systems
• Transformations - Shift data in coordinate space
− Alignment tools
• Bulk alignment
Snap - snapping based on user specified rules
Integrate – will make feature coincident within a tolerance
• Interactive(New tools introduced at 10.1)
Align Edge - snap edges together to close gaps
Align to shape - adjust layers to traced shape
Replace geometry - create an entire new shape for a feature

20. Demonstration

21. Discussion