Calculate distances and routes on geographic grids.
Package: | gdistance |
Type: | Package |
Version: | 1.1-1 |
Date: | 2011-01-04 |
License: | GPL (>=3) |
LazyLoad: | yes |
Distances can be calculated following these steps.
1. Read spatial grid data into the R environment, using the raster package. Function: raster
.
2. Construct an object of the class TransitionLayer or TransitionStack. Function: transition
.
3. Correct diagonal connections and projection distortions. Function: geoCorrection
.
4. Get coordinates for the starting and end points of routes.
5. Calculate distances and routes. Functions: accCost
,
costDistance
,
commuteDistance
,
rSPDistance
,
shortestPath
,
passage
,
pathInc
.
Ray, N. 2005. PATHMATRIX: a geographical information system tool to compute effective distances among samples. Molecular Ecology Notes 5, 177 - 180. http://cmpg.unibe.ch/software/pathmatrix/
McRae, B.H. 2006. Isolation by resistance. Evolution 60(8), 1551 - 1561.
McRae B.H., B.G. Dickson, and T. Keitt. 2008. Using circuit theory to model connectivity in ecology, evolution, and conservation. Ecology 89:2712-2724. http://www.circuitscape.org