1. NR 322: Raster Analysis I Jim Graham Fall 2008 Chapter 7

2. Types of Rasters Land Cover: forest, grass, water, roads, urban Digital Elevation Model: DEM Aerial Photos Satellite Photos Scanned: DRG, 24k Topos Derived rasters: lots!

3. Derived Rasters Land Cover from satellite and aerial Topography: Slope, aspect, hillshade Ecoregions Suitable Habitat Flood plains Geological Regions

4. Raster To Vector Satellite & Aerial –Land Cover: roads, forests, etc. –Buildings DEMs –Contours –Peaks & Valleys –Stream Networks –Watersheds

5. Vector To Raster Drawing! Points of interest Roads Water bodies Contours

6. GIS Analysis Analysis Results Raster to Vector Vector to Raster

7. Raster Analysis Topography: Slope, aspect, contours Raster Math Statistics: min, max, mean, std. dev. Distance Density Interpolation Classification Raster / Vector Conversions

8. Raster Math A matrix of pixels 1220233440 1523303139 1522293040 1420282938 1319253237 Columns Rows

9. Spatial Analyist

10. Analysis Environment Spatial Reference (Coordinate System) –Make them the same Extent –Area of interest –All rasters should overlap Cell Size –Largest of all rasters or larger

11. Spatial Analyst: General

12. Spatial Analyst: Extent

13. Spatial Analyst: Cell Size

14. Raster Calculator

15. Raster Math 12 23 129 1310 1311 1513 + = +=11213

16. Common Functions Local: –Arithmatic: +,-,/, *, MOD (Modulo): returns the remainder –Boolean: OR: If either input is true, output is true AND: If both inputs are true, output is true –CON (Conditional)

17. Mathematical Functions Abs (absolute): flips negatives to positive Ceil (ceiling): float to integer next highest integer value (i.e. 1.1 -> 2) Floor: float to integer giving next lowest integer value (i.e. 1.1 -> 1) Int (integer): truncates float to integer

18. Exponents Exp() Exp10() Ln() Log10() Max() Min() Pow() SetNull() Sqrt() Sum()

19. Comparisons <> (Not Equals) == (Equals) < (Less than) <= (Less than or equal to) > (Greater than) >= (Greater than or equal to)

20. Raster Math: Comparisons 12 23 22 32 00 01 > = >=120

21. Raster Math: Boolean AND 00 11 01 01 00 01 AND = =010 “AND” works but the calculator will insert “&”

22. Raster Math: Boolean OR 00 01 11 01 11 01 OR = =011 “OR” works but the calculator will insert “!”

23. Conditional Operator Con(,, ) Given a raster “condition”: –Puts the true value where true and false value where false Example: –Find the elevations in Rocky over 3000 meters –HighElevations=con(RockyDEM>3000,1,0)

24. Elevations over 3000 meters