RELEASE NOTES 

		spatstat 1.9-4

	 	3 August 2006

	We gratefully acknowledge Kasper Berthelsen,
	Dominic Schuhmacher and Rasmus Waagepetersen
	for substantial contributions.

OVERVIEW

	New code for perfect simulation (experimental).
	New functions for finding optimal match between point patterns.
	A new point pattern dataset.
	Further improvements to model-fitting code.
	Other minor improvements.
	
NEW FUNCTIONS

	clickppp
		interactively add points to a point pattern
		(modified from code by Dominic Schuhmacher)

	nncross
		finds nearest neighbours (and nearest neighbour distances) 
		from one point pattern to another point pattern.

	rStrauss
		perfect simulation of the Strauss process
		(code developed by Kasper Klitgaard Berthelsen)

	pppdist
		finds the optimal match between two point patterns
		according to the Wasserstein or Prohorov distance.
		(code kindly provided by Dominic Schuhmacher)

NEW DATASETS

	bei	
		Point pattern of 3605 trees in a tropical rainforest,
		with elevation data. 
		(data kindly supplied by Rasmus Waagepetersen)

IMPROVEMENTS/ENHANCEMENTS

	fitted.ppm
	predict.ppm
	qqplot.ppm
	diagnose.ppm
		These functions have new arguments 'check' and 'repair'.
		By default (check=TRUE) they check whether the format 
		of the ppm object has been damaged (which can occur 
		when it is dumped to a file and restored). By default
		(repair=TRUE) they also repair the format if it is 
		found to be damaged.

	as.psp
		Extra arguments 'from' and 'to' now enable the user
		to create a line segment pattern by specifying 
		two point patterns containing the first and second endpoints
		respectively.

	plot.owin
		Placement of main title improved.

BUGS

	[1] ppm
		Crashed with an incomprehensible error message
		when the following 3 conditions all held true:

			- data are a multitype point pattern

			- names of the types of points contain 
			strange characters like "-" and "+" 

			- model includes interpoint interaction
			which depends on types (MultiStrauss or
			MultiStraussHard).

		This occurred because characters like "-" are 
		not permitted in the names of columns of a data frame.
		Fixed.

	[2] package installation
		Some C compilers gave warnings about the declarations
		of variables in exactPdist.c and exactdist.c.
		Fixed.

	[3] plot.splitppp
		Main title was sometimes clipped.
		Fixed.