NR 322: Single Layer Analysis Jim Graham Fall 2008 Chapter 8 & 9

Geometric Calculations

Add A Field Add a double

Polyline Geometry Use an “Equidistant Projection”

Polygon Geometry Use an “Equal Area” Projection

Centroid

Making Centroids Add fields for X and Y Use “Calculate Geometry” to add the X and Y coordinates of the centroid Open the dbf in Excel Save the dbf to a tab-delimited text file Use “Tools -> Add X Y Data” to add the text file as points

Buffering Creates polygons around existing vector features

Buffering ArcToolbox -> Analysis -> Proximity -> Buffer

Buffering Create a polygon Shapefile for buffers Open the “Editor” toolbar Start an edit session Select a feature using the edit tool Task: Create new feature Target: Select “Buffer” from the “Editor” menu Enter the distance for the buffer to add around the feature

Dissolving ArcToolbox -> Data Management Tools - > Generalization -> Dissolve Combines features based on a common attribute value

Clip ArcToolbox -> Analysis Tools -> Extract - > Clip ArcToolbox -> Overlay -> Erase ArcToolbox -> Data Management Tools - > Raster -> Clip

Intersection ArcToolbox -> Analysis Tools -> Overlay -> Intersect ArcToolbox -> Spatial Analysis Tools -> Local -> Combine

Generalization ArcToolbox -> Data Management Tools - > Generalization -> …

Generalization (100 meters) OriginalGeneralized to 100 meters

Generalization (1000 meters) OriginalGeneralized to 1000 meters