### Spatial Analyst - Virginia Geospatial Extension Program

```SPATIAL ANALYST
Prepared by:
Jennifer McKee
With support from:
NSF DUE-0903270
in partnership with:
Geospatial Technician Education Through Virginia’s Community Colleges (GTEVCC)
SPATIAL ANALYST
• ArcGIS Extension
• Provides spatial analysis & modeling tools for
vector & raster data
• Examples:
– Creating new data from existing, e.g. slope or hillshade
raster from DEM
– Performing distance & cost-of-travel analyses
– Interpolate data values based on sample (point) data
HOW TO ACCESS S.A. TOOLS
• ArcToolbox
– Must search for tool if location unknown
• Model Builder
– Use tools or scripts in models
• Python
– interactive command line or script
• Raster Calculator
– for simple map algebra
S.A. TOOLSETS
• Broken down into catergories by ESRI
Conditional
Density
Distance
Extraction
Generalization
Groundwater
Hydrology
Interpolation
Local
Map Algebra
Math General
Math Bitwise
Math Logical
Math Trigonometric
Multivariate
Neighborhood
Overlay
Raster Creation
Reclass
Surface
Zonal
For greater details see ArcGIS 10 help or online resource center
ACCESSING S.A. TOOLS
RASTER CALCULATOR
• Simple Math Algebra
• Use interface –
correct syntax is
required, including
spaces
R.C. EXAMPLE
• Want to query DEM to locate all areas with 600
meters or greater elevation
"eggleston" >= 600
• Results in boolean output: 1 = true, 0 = false
R.C. EXAMPLE CONTINUED
• Combining multiple boolean outputs to find an area that
• For example: you want to identify areas that have
elevation >= 600 meters & have a slope >= 30%
1.
2.
3.
1.
•
•
"eggleston" >= 600
"Slope" >= 30
"Above600m" & "slopeabove30“
OR
("eggleston" >= 600) & ("Slope" >= 30)
2 separate queries for each criteria & then combine
boolean outputs
1 compound query for both criteria
EXERCISES
• Already performed vector based spatial analysis
on Day 2 during Rodney’s Multi-Criteria
Evaluation
• GIS Tutorial 2 Spatial Analysis
–
–
–
–
–
Tutorial 3-1 pg. 76
Tutorial 3-3 pg. 93
Tutorial 5-1 pg. 124
Tutorial 5-8 pg. 179
Tutorial 5-9 pg. 191
• MCE with Spatial Analyst (Auxiliary Materials
notebook, Section 6)
```