## R Analytical Environment

Read and write ESRI Shape Files

Demonstrates techniques from three R packages for reading, displaying, and writing ESRI Shapefiles

Display R Spatial Objects with Google Maps / Google Earth

Demonstrates creation of Keyhole Markup Language (KML) files for vector ESRI Shape Files and raster GeoTIFF files, enabling their display in GoogleEarth / Google Maps

Read and Display Data from GPS Devices Using R

Two examples demonstrate the use of the R environment to process data sets from GPS devices: Read/Translate/Display/Write ASCII Point Files.

Point-in-Polygon Assignment to Point Data Set Members

Associate points in a data set with the polygons in a second data set that surround them

Compute Shortest Path between points in Euclidean Space

Compute a matrix of shortest-path distances between spatially-referenced points in a region

Overlay Points on Satellite Image / Extract Pixel Values

Use R geospatial classes to assign MODIS Image temperature values to georeferenced point locations.

Sampling Vector Polygon Data Using Point Grid Overlay

Overlay a regularly-spaced grid of points on the Bailey's Ecoregions map of the United States, and extract the Bailey's region number underneath each point.

Compute Centroids for a Polygon set

Demonstrates computation of Centroid (Center of Gravity) points for a polygon data set stored in an ESRI Shape File

Compute Convex Hull/Region of Interest Polygons for Point Data Sets

Given a point data set AND a polygon data set whose members surround the point set members: 1) Compute the polygon areas; 2) assign each point its 'bounding polygon'; 3) calculate the convex hull bounding the point data set; 4) generate Region of Interest (ROI) polygons surrounding each point data set member

Explore the relationships of spatially coincident point and polygon data layers using R geospatial tools

Assign Closest Points to members of a separate point data set

Input two geocoded point data sets from .csv files into R workspace, then assign to one data set the closest point locations from the other

Aggregate spatial data polygons into larger polygons along with their descriptive attributes, using a spatial primary key

Join and Query Relational Data Tables With R

Join and perform relational queries on multiple attribute tables. Compute summary statistics using the joined tables.

Create Maps With R Geospatial Classes and Graphics Tools

Generate various types of publication-quality maps using standard R graphics tools

Cartographical Map Projections: A Discussion

A comprehensive introduction to the art, science, and application of map projections

Integrate C Language Function Into R With an R Package

A step-by-step tutorial, including a complete, downloadable example, demonstrating the creation and use of an R package that calls a C function performing simple matrix calculations

## ESRI ArcMap GIS

ArcMap GIS: Use Mouse to Point/Click/Extract Image Values From Raster Data Layer (12 kb Pdf)

Change the Latitude/Longitude display units and extract single-pixel values using the mouse

ArcMap GIS Overlay Polygon Coverage Generation (33 kb Pdf)

Create a Point Shape File attribute file by performing a series of Spatial Join operations

ESRI ArcMap GIS Spatial Overlay Analysis (31 kb Pdf)

Use Polygon Shape Files to perform raster data set clipping operations

Interactively Extract and Save Arc Map GIS Shape File Subset (9 kb Pdf)

Use the mouse to select and write a subset of existing ESRI Shape File to new Shapefile