pppmatching
Create a Point Matching
Creates an object of class "pppmatching" representing
a matching of two planar point patterns (objects of class "ppp").
Usage
pppmatching(X, Y, am, type = NULL, cutoff = NULL, q = NULL,
mdist = NULL)Arguments
- X,Y
Two point patterns (objects of class
"ppp").- am
An
npoints(X)bynpoints(Y)matrix with entries \(\geq 0\) that specifies which points are matched and with what weight; alternatively, an object that can be coerced to this form byas.matrix.- type
A character string giving the type of the matching. One of
"spa","ace"or"mat", orNULLfor a generic or unknown matching.- cutoff, q
Numerical values specifying the cutoff value \(> 0\) for interpoint distances and the order \(q \in [1,\infty]\) of the average that is applied to them.
NULLif not applicable or unknown.- mdist
Numerical value for the distance to be associated with the matching.
Details
The argument am is interpreted as a "generalized adjacency matrix":
if the [i,j]-th entry is positive, then the i-th point
of X and the j-th point of Y are matched and the
value of the entry gives the corresponding weight of the match. For
an unweighted matching all the weights should be set to \(1\).
The remaining arguments are optional and allow to save
additional information about the matching. See the help files for
pppdist and matchingdist for details on
the meaning of these parameters.
See Also
Examples
# NOT RUN {
# a random unweighted complete matching
X <- runifpoint(10)
Y <- runifpoint(10)
am <- r2dtable(1, rep(1,10), rep(1,10))[[1]]
# generates a random permutation matrix
m <- pppmatching(X, Y, am)
summary(m)
m$matrix
plot(m)
# a random weighted complete matching
X <- runifpoint(7)
Y <- runifpoint(7)
am <- r2dtable(1, rep(10,7), rep(10,7))[[1]]/10
# generates a random doubly stochastic matrix
m2 <- pppmatching(X, Y, am)
summary(m2)
m2$matrix
plot(m2)
m3 <- pppmatching(X, Y, am, "ace")
m4 <- pppmatching(X, Y, am, "mat")
# }