pointpats.L

class pointpats.L(pp, intervals=10, dmin=0.0, dmax=None, d=None)[source]

Estimates the \(L\) function for a point pattern [OSullivanU10].

Parameters
ppPointPattern

Point Pattern instance.

intervalsint

The length of distance domain sequence.

dminfloat

The minimum of the distance domain.

dmaxfloat

The maximum of the distance domain.

dsequence

The distance domain sequence. If d is specified, intervals, dmin and dmax are ignored.

Notes

In the analysis of planar point processes, the \(L\) function is a scaled version of \(K\) function. Its estimate is also typically compared to the value expected from a process that displays complete spatial randomness (CSR):

\[L(d) = \sqrt{\frac{K(d)}{\pi}}-d\]

where \(K(d)\) is the estimator for the \(K\) function and \(d\) is distance.

The expectation under the null of CSR is 0 (a horizonal line at 0). For a clustered pattern, the empirical \(L\) function will be above the expectation, while for a uniform pattern the empirical function falls below the expectation.

Attributes
darray

The distance domain sequence.

larray

L function over d.

__init__(self, pp, intervals=10, dmin=0.0, dmax=None, d=None)[source]

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__(self, pp[, intervals, dmin, dmax, d])

Initialize self.

plot(self)

Plot the distance function

plot(self)[source]

Plot the distance function

Parameters
qq: Boolean

If False the statistic is plotted against distance. If Frue, the quantile-quantile plot is generated, observed vs. CSR.