integral_peak: Computes integral of a very peaked function, modified from...

In DAISIE: Dynamical Assembly of Islands by Speciation, Immigration and Extinction

Computes integral of a very peaked function, modified from the SADISA package

Description

computes the logarithm of the integral of exp(logfun) from 0 to Inf under the following assumptions:

• "exp(logfun)" has a single, sharply peaked maximum

• "exp(logfun)" is increasing to the left of the peak and decreasing to the right of the peak

• "exp(logfun)" can be zero or positive at zero

• "exp(logfun)" tends to zero at infinity

Usage

integral_peak(
  logfun,
  xx = seq(-20, 20, 2),
  xcutoff = 2,
  ymaxthreshold = 1e-12,
  pars1,
  pars2,
  brts,
  stac,
  missnumspec,
  methode,
  abstolint,
  reltolint,
  verbose,
  pick,
  par_mean,
  par_sd,
  par_upper_bound
)

Arguments

logfun	the logarithm of the function to integrate
xx	the initial set of points on which to evaluate the function
xcutoff	when the maximum has been found among the xx, this parameter sets the width of the interval to find the maximum in
ymaxthreshold	sets the deviation allowed in finding the maximum among the xx

Value

the result of the integration

References

Haegeman, B. & R.S. Etienne (2017). A general sampling formula for community structure data. Methods in Ecology & Evolution 8: 1506-1519. https://doi.org/10.1111/2041-210X.12807

DAISIE documentation built on Oct. 22, 2023, 1:06 a.m.