Evaluate Expression Involving Components of a Measure
An expression involving the names of components of a measure is evaluated.
## S3 method for class 'msr' with(data, expr, ...)
data |
A measure (object of class |
expr |
An expression to be evaluated. |
... |
Ignored. |
This is a method for the generic function
with for the class "msr".
The argument data should be an object of class "msr"
representing a measure (a function which assigns a value to each
subset of two-dimensional space).
This function can be used to extract the components of the measure, or to perform more complicated manipulations of the components.
The argument expr should be an un-evaluated expression
in the R language. The expression may involve any of the variable
names listed below with their corresponding meanings.
qlocations |
(point pattern) all quadrature locations |
qweights |
(numeric) all quadrature weights |
density |
(numeric) density value at each quadrature point |
discrete |
(numeric) discrete mass at each quadrature point |
continuous |
(numeric) increment of continuous component |
increment |
(numeric) increment of measure |
is.atom |
(logical) whether quadrature point is an atom |
atoms |
(point pattern) locations of atoms |
atommass |
(numeric) massess of atoms |
The measure is the sum of discrete and continuous components. The discrete component assigns non-zero mass to several points called atoms. The continuous component has a density which should be integrated over a region to determine the value for that region.
An object of class "msr" approximates the continuous component
by a sum over quadrature points. The quadrature points are chosen
so that they include the atoms of the measure. In the list above,
we have increment = continuous + discrete,
continuous = density * qweights,
is.atom = (discrete > 0),
atoms = qlocations[is.atom] and
atommass = discrete[is.atom].
The result of evaluating the expression could be an object of any kind.
Adrian Baddeley Adrian.Baddeley@curtin.edu.au, Rolf Turner r.turner@auckland.ac.nz and Ege Rubak rubak@math.aau.dk.
X <- rpoispp(function(x,y) { exp(3+3*x) })
fit <- ppm(X, ~x+y)
rp <- residuals(fit, type="pearson")
with(rp, atoms)
with(rp, qlocations %mark% continuous)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.