### What is *RCALI*?

*RCALI* is a

R package that makes
interface between

CaliFloPP and

R.

*CaliFloPP* is
a software that calculates flows of particles between
pairs of polygons, when given a so-called individual dispersal
function. The individual dispersal function describes the particle
dispersion between pairs of points, and

*CaliFloPP*
deduces the total
flows between pairs of polygons.

Moreover,

*RCALI* allows to take into account the angle of the
current point with the horizontal, and so, to analyze anisotropic dispersal function.

This package is developed in the MaIAGE Lab. of INRA - Jouy-en-Josas,
France.

### Some more details

The integration problem is solved by
reducing the dimension of the integral and by using algorithms from
computational geometry.

Two general methods for numerical integration are implemented:

- a simple randomized discretization of the integral,
- an two-dimensional adaptive cubature method.

The first method, denoted by grid method,
involves simple discretizations of the integral based
on regular grids. The approximation is an unbiased
estimator of the integral. Furthermore,
by using independent replicates,
it is possible to assess the precision of the result. This method is
quite robust (it is unbias and converges even for non-smooth
integrands) but it is rather time consuming.

The second method is based on
the algorithm

DCUTRI. The approximation errors are estimated.
Compared to the grid method, this method is
very fast.

### Input and output

**Input:**
The user should provide the polygons coordinates in a text file.
He can define his own individual dispersal functions in R or
by customizing C-programs.

**Output:**
The results are output on the screen (or standard output unit),
and/or on a result-file.

### References

#### Main reference paper

**A. Bouvier, K. Kiêu, K. Adamczyk, and H. Monod.**
Computation of integrated flow of particles between polygons.

*Environmental Modelling & Software*,
24:843--849, 2009.
[

DOI|

http]

#### Other reference

**J. Berntsen, T.O Espelid.**
DCUTRI: Algorithm 706, An algorithm for adaptive cubature over a
collection of triangles.
*ACM Transactions on Mathematical Software*,
18(3):329--342, 1992.
Copyright © 2011-
INRA. All rights
reserved.

*RCALI* is an open source, freely available software released under
the CeCILL-C
Licence.
Please, read the LICENSE file.

R
system, a C compiler, and
the R-package *splancs*.

An
introduction and other documents
are provided in the directory `doc` of the package.

Download the last version
here (uncompress the file before installation)
or
from the CRAN
site.

* 2017-03-03: What's new in *RCALI version 0.2-18*

Annie.Bouvier at
inra.fr