spatialsegregation-ISAR {spatialsegregation} | R Documentation |
Compute the Individual Species Area Relationship ( ISAR ) for a given multitype point pattern.
isarF(pp, parvec = 1:20, graph_type = "knn", type = NULL, ...) isar_index(pp, graph_type = "knn", graph_par = 4, type = NULL, ...)
pp |
Multitype point pattern (see package 'spatstat') |
parvec |
Default 1:20. Vector for the neighbourhood defining graph, e.g. geometric graph with different r . |
graph_type |
Default knn . Type of the neighbourhood graph. Accepts: knn , geometric , delauney , gabriel . |
type |
Default NULL. Calculate only for type 'type'. If NULL compute mean over all types. |
graph_par |
The single parameter to calculate the value in. |
... |
Further tuning parametes for the function segregationFun. |
Date: | 2009-03-04 |
License: | GPL v2 or later |
Extension of ISAR-function introduced in WGGH 2007. In effect calculates the expected amount of different types present in the neighbourhood of a typical point.
The function isarF
is the main calculation function. Uses function 'segregationFun' with parameter ftype=4
.
The function isar_index
is a shortcut to get a single value for the pattern. Uses 4-nn graph by default.
Tuomas Rajala University of Jyvaskyla, Finland tarajala@maths.jyu.fi
Rajala, Illian: Graph-based description of mingling and segregation in multitype spatial point patterns. To appear 2009.
Wiegand, Gunatilleke, Gunatilleke, Huth: How individual species structure diversity in tropical forests. PNAS, nov 16, 2007.