siplab (version 1.0)

efficiency: Efficiency Functions

Description

Compute efficiency values depending on distance and plant marks, for use in assimilation.

Usage

flat.eff(dx, dy, marks, par = NULL)
tass.eff(dx, dy, marks, par = list(b = 3.52 * 0.975, c = 6.1, smark = 1))
gates.eff(dx, dy, marks, par = list(a = 1, b = 4, smark = 1))
gnomon.eff(dx, dy, marks, par = list(a = 1, b = 4, smark = 1))

Arguments

dx

Vector of x-distances. Points x-coordinates minus plant x-coordinate.

dy

Vector of y-distances. Points y-coordinates minus plant y-coordinate.

marks

Plant mark information.

par

Vector or list of parameters.

Value

• Vector of efficiency values, of length equal to the length of dx and dy.

encoding

UTF-8

Details

The values of par must be given in the argument effpar of assimilation, they are shown here as examples.

smark in par indicates the location of the plant size variable in marks. It can be a data frame column number, or a string id like "height".

flat.eff returns 1, independently of plant size or distance.

tass.eff, gates.eff, and gnomon.eff are proportional to their influence function counterparts (see influence), scaled to be 1 at the origin.

References

http://forestgrowth.unbc.ca/siplab

García{Garcia}, O. A generic approach to spatial individual-based modelling and simulation of plant communities. Manuscript in review.

See Also

assimilation, influence