2013-04-09  Gregory Soyez  <soyez@fastjet.fr>

	* Release of SISCone 2.0.6

 	* NEWS, doc/html/index.html
	  set the release date to April 9th

2013-04-08  Gregory Soyez  <soyez@fastjet.fr>

	* doc/html/*.html:
	* configure.ac:
	  switched version number to 2.0.6

	* NEWS:
	  preparing for SISCone 2.0.6

	* setversion.sh: minor fix (used bash instead of sh)

	* CHECKLIST:   *** ADDED ***
	  helper checklist for the release process

2013-04-06  Gavin Salam  <gavin.salam@cern.ch>

	* configure.ac: 
	  updated minimal required autotools version to 2.63

2013-02-05  Gavin Salam  <gavin.salam@cern.ch>

	* autogen.sh: tried to be more tolerant of different libtool
	  versions (some take --version, others -V). Still have problems
	  on OS X 10.8 with macports , but autoreconf works fine.

	* configure.ac: 
	  replaced AM_CONFIG_HEADER with with AC_CONFIG_HEADERS, following
	  error with autoconf 2.69 on OS X 10.8 with macports.

2013-02-04  Gregory Soyez  <soyez@fastjet.fr>

	* siscone/Makefile.am:
	  do not install config.h

	* siscone/spherical/Makefile.am:
	  fixed directory for headers installation for the spherical
	  version of SISCone

2012-01-17  Gregory Soyez  <soyez@fastjet.fr>

	* NEWS:
	  SISCone 2.0.5

	* NEWS:
	* configure.ac:
	* Doxyfile:
	  prepared for the release of SISCone 2.0.5

	* siscone/spherical/Makefile.qm:
	  used $(includedir) instead of $(prefix)/include

2012-01-13  Gregory Soyez  <soyez@fastjet.fr>

	* siscone/Makefile.am:
	  used $(includedir) instead of $(prefix)/include

2011-11-25  Gregory Soyez  <soyez@fastjet.fr>

	* NEWS:
	  SISCone 2.0.4

	* NEWS:
	  updated in preparation for the 2.0.4 release

	* doc/html/home.png:             *** ADDED ***
	* doc/html/usage.html:
	* siscone/siscone_error.h:
	* doc/html/index.html:
	  fixed typos; updated html links.

	* configure.ac:
	* Doxyfile:
	* doc/html/*.html:
	  updated the version number to 2.0.4 and the release information

	* siscone/spherical/siscone.cpp:
	* siscone/spherical/siscone.h:
	* siscone/siscone.cpp:
	* siscone/siscone.h:
	  allowed to redirect the banner to a different stream than cout

2011-11-16  Gregory Soyez  <soyez@fastjet.fr>

	* examples/test.cpp:
	  cast a vector size (of type size_t) onto unsigned int to avoid a
	  compiler warning (on either 32 or 64-bit machines)

2011-11-15  Gavin Salam  <salam@lpthe.jussieu.fr>

	* AUTHORS: 
	  updated my address. 

2011-11-15  Gregory Soyez  <soyez@fastjet.fr>

	* siscone/protocones.cpp (is_inside, proceed_with_stability):
	* siscone/spherical/split_merge.cpp (init):
	* siscone/split_merge.cpp (init):
	* siscone/siscone_error.h:
	* siscone/area.cpp (compute*_areas):
	  renamed or commented out a few local variables and method
	  arguments to avoid shadowing class members (gcc -Wshadow)

	* examples/spherical.cpp:
	* examples/sample.cpp:
	  removed unused argc, argv parameters

	* examples/spherical.cpp:
	* examples/sample.cpp:
	* examples/times.cpp:
	* examples/test.cpp:
	* examples/area.cpp:
	* examples/main.cpp:
	* siscone/spherical/split_merge.cpp (save_contents, show):
	* siscone/split_merge.cpp (save_contents, show):
	* siscone/quadtree.cpp (save, save_leaves):
	  got rid of a few format warnings by replacing %le and %lf by %e
	  and %f (the l prefix applying to int and unsigned int) + a couple
	  of signed/unsigned mismatches (%d -> %u)

	* configure.ac:
	  switched version number to 2.0.4-devel

2011-10-05  Gregory Soyez  <soyez@fastjet.fr>

	* NEWS:
	  SISCone 2.0.3

	* AUTHORS:
	  updated addresses and phone numbers

	* configure.ac:
	* Doxyfile:
	* doc/html/*.html:
	  updated the version number and the release information

	* Doxyfile:
	  removed the treeview

	* siscone/reference.cpp:
	  removed redundant operator + (following a gcc warning)
	  Checked with FastJet's regression check that it was indeed not
	  used

	* siscone/spherical/protocones.cpp:
	  removed an unused variable

2011-08-09  Gregory Soyez  <soyez@fastjet.fr>

	* siscone/spherical/split_merge.h:
	  fixed the description of E_tilde. It was
             sum of E_i [ 1 + sin^2(theta_iJ) ]
	  but in practice we used
             sum of E_i [ 1 +|p_i x p_J|^2/(|p_i|^2 E_J^2)]
  	  as mentioned further down in the ChangeLog (that avoids
	  potential issues when a protojet has a zero 3-momentum)

2011-05-17  Gregory Soyez  <soyez@fastjet.fr>

	* configure.ac, Doxyfile & NEWS:
	  SISCone 2.0.2

2010-10-27  Gregory Soyez  <soyez@cern.ch>

	* siscone/makefile.static:
	  recursed make clean in the spherical dir

	* siscone/spherical/makefile.static:
	  included main siscone header directory

	* siscone/siscone.cpp, siscone/spherical/siscone.cpp:
	  The config.h header should be present from autoheader in the
	  autotools build and from the sed command in the main
	  makefile.static for build using the static makefiles.

2009-05-29  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* configure.ac & NEWS: 
	  SISCone 2.0.1

2009-05-28  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* Doxyfile (PROJECT_NUMBER): 
	  doc/html/*.html:
	  switched the version number to 2.0.1

	* INSTALL (Notes): 
	  fixed the comment on the static/shared default build

	* configure.ac: 
	  enabled shared libs by defaut (following a long discussion
	  regarding static vs. shared libraries, we finally decided to
	  make a minimal modification compared to the previous release,
	  i.e. keep shared libraries on)

2009-05-25  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* configure.ac: 
	  switched back to static libraries

	* siscone/Makefile.am:
	  examples/Makefile.am:
	  siscone/spherical/Makefile.am:
	  replace a few ${var} by $(var) to be more compatible 
	  with Makefile rules


2009-05-01  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/spherical/hash.cpp (siscone_spherical): 
          renamed _R into _radius (problem with some Mac systems).  
	  Note: some of the comments were mentioning R2 as a parameter
	  rather than R, so this has been fixed at the same time.

	* configure.ac:
	  build shared libs by default
	  This is a bug-fix for FastJet that now uses shared libs by
	  default too
	
	* configure.ac & Doxyfile:
	  switched version number to 2.0.1-devel

2009-04-17  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* NEWS & configure.ac: 
	  SISCone 2.0.0

	* doc/html/index.html: 
	  Doxyfile:
	  configure.ac:
	  switched the version number to 2.0.0

2009-03-17  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/split_merge.cpp (siscone): 
          moved the computation of the rapidity limits AFTER the 
	  exclusion of the particles with pz>=E
	

2009-03-12  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* configure.ac: 
	  switched version to 2.0-devel

	* NEWS: 
	  updated to include the new things in the upcoming release

	* Doxyfile:
	  updated together with an additional bunch of doxygen-compliant
	  comments in the source files

	
2008-08-06  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/siscone.cpp (siscone): 
	  make sure that the full 4-vector information is included in the
	  protocones list.

	
2008-07-29  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/siscone.cpp: 
	  siscone/spherical/siscone.cpp: 
	  check that the config.h file is available.
	  Otherwise, use fixed values for PACKAGE and VERSION.
	

2008-07-23  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/spherical/siscone.h (siscone_spherical): 
	  set E_tilde as the default SM variable.

	* siscone/spherical/split_merge.{h,cpp} (siscone_spherical): 

	  addressed the issue of IRC safety related to the choice of the
	  split-merge ordering variable. We kept E (an unsafe choice) for
	  its simplicity and added E_tilde defined as
	
                              /      |p_i X p_J|^2  \
	    \sum_{i\in J} E_i | 1 + --------------- |
	                      \      |p_i|^2 E_J^2  /

	  The use of E_J instead of p_J in the denominator prevents the
	  case where jets have zero momentum (e.g. monster jets with
	  momentum conservation)
	
	  Note that this variable is only used for the ordering; the
	  computation of the overlap is always using the energy.
	 
	
2008-07-18  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/siscone.cpp (siscone)
	  siscone/spherical/siscone.cpp (siscone_spherical): 
	  package_name() returns PACKAGE_NAME, not VERSION!

	* siscone/spherical/Makefile.am: 
	  added a path for siscone/config.h to be correctly included

	* siscone/Makefile.am:
	  prevent config.h from being shipped with the distribution
	

2008-07-07  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/spherical/split_merge.cpp (siscone_spherical): 
	  transformed the pt2 cut-off on particles into an 
	  energy (squared) cut-off.
	

2008-07-07  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* Spherical version included in the main trunk
	  (see below for details)

	* Copied the 'spherical branch' into the siscone/spherical
          folder.
	  Copied the sample program into the example folder.
	  Imported the ChangeLog from the branch
	  
	  Steps remaining in the main trunk: (. = todo, - = done)
           - updating the makefiles
	   - deleted the "defines.h" file in the subdir
	     the main one is used.
           - tested (make distcheck + sample running)

          Questions:
           - do we also copy the unchanged files? (It will mess a bit the
             filenames but they concerns material hidden to the end-user,
             so I'd keep them in the trunk
             It concerns circulator, reference, ranlux and siscone_error.
           - do we remove the quadtree in the spherical dir? 
	     (I'd say 'yes', not done currently)
           - keep the "unused" files in the branch? (area, quadtree, ...)


2008-07-02  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

        * started the process of merging the spherical version of SISCone
          into the main trunk. The new version will be inserted in the
          "siscone/spherical" directory. We shall put it under the
          'siscone_spherical' namespace and rename the relevant classes
          using a 'CSph' prefic instead of the 'C' prefix used in the main
          trunk.
          Steps to be done in the branch: (. = todo, - = done)
           - move the relevant files in a 'siscone/spherical' directory
           - add a siscone/Makefile.am in the branch (+small updates)
           - change the namespace
           - rename the classes and update the names in the code
             Note that some of the classes have been kept from the main
             version (e.g. everything in reference.h, siscone_error.h +
             isolated classes like circulator, two_vector). This should
             not affect the end-user.
           - in the examples, move the main sample into a 'spherical' one
           - test on the branch
          DONE.
	
2008-06-16  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

        * siscone/vicinity.cpp (siscone): revised the normalisation of the
          cocircular range.

        * siscone/split_merge.cpp (siscone): recomputed the norm of
          the result of a collinear merging. This is required as
          the norm is used in stable-cone search and not recomputed
          automatically.

        * siscone/protocones.cpp (siscone): normalised directions
          used to determine the angles. This might well be the reason
          of the co-circular problem.

        * siscone/geom_2d.cpp (siscone): removed an unused variable


2008-06-14  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

        * Note: this version passed ~3e8 safety tests (including arcs,
                soft particles, reordering and single/multi-pass).

        * siscone/vicinity.cpp (siscone): added cocirc-tests
          WARNING: this is a naive adaptation from the cylindrical case.

        * siscone/momentum.h (siscone): reverted most of the last
          modification: since the simple computation using a cos()
          requires the computation of the norm (not its squared because
          the sign of the cos matters) it is most complicated than the one
          with the tangent. Note that we're free of the problem mentionned
          below as the only place where it can happen is in the
          computation of the vicinity and there we compute distances
          internally rather than calling is_closer.
          Finally, we've added a is_closer_safe with the computation
          using te cosine.

2008-06-13  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>
        * siscone/vicinity.cpp (siscone):
          pre-added co-circularity management

        * siscone/momentum.h (siscone):
          replaced the tangent used in distances comparison by
          a cosine (the tangent is more precise at small R but
          we'll probably never get down to that small values of R).
          The reason for the replacement is that it gives wrong
          results for vicinity computation for 2R>pi/2.
          This present computation is also faster (no x-product).

          All calls to that function have been updated too.


2008-06-12  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

        * Description: this is the first complete adaptation to the
          SISCone jet-search using spherical coordinatee.
          This branch is motivated by potential applications to
          cosmic-rays and follows a request by Yvonne Kssel
          <Yvonne.Kuessel@gmx.de>

        * Summary of modifications:
          - use the distance on a sphere instead of the eta-phi one This
            is the most important change and comes with
            modifications... well...  ... everywhere. Most of the infos
            about the distance are in the momentum.{h,cpp} files.  There
            are other important pieces when computing the candidate
            centres (in vicinity.cpp). And the theta_phi range (previously
            eta_phi!)  in geom2d.cpp has also been relooked.
          - The spit--merge(SM) uses the energy instead of pttilde by
            default for the ordering
          - The final jets ae ordered in E instead of pt.
          - we don't remove particles with infinite rapidity (both in SC
            search and SM)
          - for the cone consistency tests, we use |px|+|py|+|pz| instead
            of |px|+|py|
          - we have removed the cut on soft particles in
            Csplit_merge::merge_collinear_and_remove_soft() since it was
            mainly used for area speed up.
          - Csplit_merge::use_pt_weighted_splitting is replaced by
            Csplit_merge::use_E_weighted_splitting when it is defined, the
            weight is of course 1/E^2 instead of 1/pt^2
          - To emphasise the fact that this is not the main SISCone trunk,
            we've added one sentence in the header of every file and a
            WARNING in the SISCone banner.

        * Still to be done
          - implement co-circularity (currently the range is set to 0)
          - in the split--merge, check the precision of the collinearity
            test?

        * Other points to think about
          - for the split of 2 protojets, we're currently making many
            calls to a full distance computation. This can surely be
            improved when no weighting is asked...
          - completely remove the quadtree?
          - remove the area support?
          - remove the Ctheta_phi range?
            or improve it (the cell initialisation assume a square shape,
            not a circle, but already with a square, the geometry is
            rather involved)

        * Final word: still need a whole bunch of tests (noticeably IRC
          safety, speed). Note that the stable-cone search has been
          checked "graphically".


2008-05-20  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/hash.cpp (siscone): 
	  Adapted the size of the hash to scale like Nn(=N^2R^2) instead
	  of N^2. This allows to save a fair amount of memory.
	

2008-05-16  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* siscone/defines.h
	  siscone/hash.{h,cpp} (siscone)
	  siscone/protocones.{h,cpp} (siscone):
	  siscone/siscone.{h,cpp} (siscone):
	  add some debug information about the occupancy of the hash
	  when DEBUG_STABLE_CONES is defined

	* examples/test.cpp: update the code to use Csiscone directly
	  instead of separate calls to stable cone search and split--merge
	  stage. This should be less confusing for end-users.

2008-05-15  Gregory Soyez  <gsoyez@quark.phy.bnl.gov>

	* configure.ac: 
	  in the last CXXFLAGS fix, the default has been set at a wrong
	  place (practically, CXXFLAGS was set to the system default value
	  -O2 -g and thus not replaced with our local default).
	  This is fixed now.

2008-03-24  Gregory Soyez  <g.soyez@ulg.ac.be>

        * configure.ac:
          fix CXXFLAGS in such a way as to allow the user to set their own
          default.

	
2008-03-17  Gregory Soyez  <g.soyez@ulg.ac.be>

	* siscone/defines.h:
	  siscone/siscone.h/cpp
	  examples/option.cpp
	  BUGS:
	  Because of potentil conflicts with other packages, the 
	  tags defined in config.h are no longer included in 
	  defines.h but only in SISCone source files. 
	  As a practical consequence, the program name and version 
	  number are now accessed through siscone_package_name() and
	  siscone_version() both defined in siscone.h and inside
	  the siscone namespace. See examples/options.cpp for 
	  an example.
	  This solves the corresponding bug reported by Seuster.
	

2008-03-15  Gavin Salam  <salam@lpthe.jussieu.fr>

	* BUGS: 
	  added entry related to PACKAGE/VERSION/etc reported by Seuster. 

2008-03-12  Gregory Soyez  <g.soyez@ulg.ac.be>

	* siscone/split_merge.h/cpp (siscone):

	  This is a non-negligible modification: we have added the
	  possibility to modify the way particles are split during the
	  split-merge step. 
	  Assume one has to split protojets 1 and 2. The standard split
	  associates a common particle j to the closest centre
	  i.e. compares the distances D_{1j} vs. D_{2j}. 
	  Now, by calling Csplit_merge::set_pt_weighted_splitting(true),
	  it is possible to perform the splitting according to the anti-kt
	  distance i.e. comparing D_{1j}/k_{t1} vs. D_{2j}/k_{t2}.
	  This new option should allow to produce more
	  rigid (soft-resilient) jets.
	  Note that the default is to use the standard distance comparison
	  so backward compatibility is not broken.

	
2008-03-11  Gregory Soyez  <g.soyez@ulg.ac.be>

	* siscone/area.cpp (siscone): 
	  the jet+area finding now really returns the number of jets 
	  as does the standard clustering

	* siscone/area.cpp (siscone): 
	  don't include ghosts in stable-cone search when only the 
	  passive area is requested.
	  This is a huge speed improvement as the execution time (when
	  only passive area is requested) is now (with Ntot = N+Nghosts)
	    O(N^2 log(N) +  Ntot^2)
	  instead of
	    O(Ntot^2 log(Ntot) +  Ntot^2)

	* configure.ac: 
	  switched the main trunk to SISCone-1.4.0-devel
	

2008-03-07  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* configure.ac: 
	  switched version to 1.3.1

2008-01-17  Gavin Salam  <salam@lpthe.jussieu.fr>

	* configure.ac: 
	  switched version number over to 1.3.1-devel

2008-01-15  Gregory Soyez  <g.soyez@ulg.ac.be>

	* siscone/geom_2d.h (M_PI): 
	  added definition of M_PI if needed (VC compilation)

	* siscone/protocones.cpp (siscone): 
	  added the algorithm header (VC compilation)

2007-11-12  Gregory Soyez  <g.soyez@ulg.ac.be>

	* NEWS & configure.ac:
	  SISCone 1.3.0
	

2007-11-10  Gavin Salam  <salam@lpthe.jussieu.fr>

	* configure.ac: 
	* examples/Makefile.am: 
	* examples/events/Makefile.am: 
          made sure some sample events were included in the dist
	
2007-11-07  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* configure.ac: 
	  switched +="" to A=A"" to eliminate an error on mac

2007-10-24  Gregory Soyez  <g.soyez@ulg.ac.be>

	* examples/options.cpp: fix a missing "siscone/" in header include

	* examples/Makefile.am: fix a problem with make distcheck

	* configure.ac: the --enable-shared cmd-line option is already
	  handled by libtool. We just need to add AM_DISABLE_SHARED to
	  disable the shared lib by default (can still be changed by using
	  --enable-shared)
	  Also, we set the minimal version of autoconf to 2.57.

	* examples/Makefile.am: do not install anything (just build
	  examples locally)

	* examples/main.cpp (main): print a more specific error message
	  when the event file cannot be opened

	
2007-10-03  Gregory Soyez  <g.soyez@ulg.ac.be>

	* siscone/defines.h: read available information from config.h

	* In examples, include headers from the 'siscone' folder

	* Move the src folder into a new 'siscone' folder

	
2007-10-02  Gregory Soyez  <g.soyez@ulg.ac.be>

	* add configure script for the build process. This comes with a
	  bunch of new files: autogen.sh, configure.ac, and a Makefile.am
	  in each directory. See the INSTALL files for more details

	* replace each Makefile by makefile.static
	  Makefile-based build is now made through 
	    make -f makefile.static

	* examples/area.cpp: add a sample program for SISCone jet area
	  computation

	
2007-06-24  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/defines.h: SISCone 1.2.0
	

2007-06-15  Gregory Soyez  <g.soyez@ulg.ac.be>


	* src/geom_2d.h/cpp: use a 32x32 eta-phi-plane tiling. The range
	  is then defined by two binary fields. This allows easy overlap
	  test and merging. For protojets splitting, the new ranges are
	  built by adding particles one-by-one.

	* src/split_merge.cpp (siscone): 
	  - align code with the modifications in geom_2d.h/cpp
	  - the output of save_contents has slightly been improved

	* src/area.h/cpp: add methods to compute only the active or passive
	  area

	* examples/main.cpp: add pass-by-pass statistics in the verbose
	  output

	* examples/options.cpp: fix bug when passing an unknown long
	  option to getopt_long


2007-06-02  Gregory Soyez  <g.soyez@ulg.ac.be>

	* examples/sample.cpp: add a few lines to show how one can browse
	  the output jets of compute_jets.

	* examples/times.cpp: only save runtime using the siscone class
	  instead of a separate determination.
	
2007-05-09  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  soft_pt2_cutoff -> stable_cone_soft_pt2_cutoff
	  fixed infinite loop for non-zero stable_cone_soft_pt2_cutoff

2007-05-09  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/split_merge.cpp|h:
	  When building the list of particles to be passed to stable-cone
	  search, allow to remove particles below a pt2 threshold
	  soft_pt2_cutoff.

2007-04-27  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* src/geom_2d.cpp: 
	  corrected bugs in range_union -- now passes test that 1000
	  events are identical to what we had previously.

2007-04-26  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/split_merge.cpp (siscone): add range support to the
	  split--merge. When computing overlap, we first check that the
	  two ranges overlap. In splitting, ranges are set to the parent
	  ranges. In merging, range is set as the union of the parent
	  ranges.

	* src/split_merge.h: add a range variable to the Cjet class

	* src/geom_2d.cpp/h (siscone): add the Ceta_phi_range to handle
	  covering ranges in the ete-phi plane. This goes with a function
	  to test overlap and another to compute union.

	* src/momentum.h: Move geometry tools into geom_2d.h (new file)
	

2007-04-24  Gavin SALAM  <salam@lpthe.jussieu.fr> + Matteo

	* src/defines.h (VERSION): 
	  updated version number to 1.1.2-devel 

	* src/split_merge.cpp (include): 
	  moved test on SM_var2_hardest_cut_off to beginning of loop, to
	  ensure that we don't get a first jet that's below the cutoff.
	
2007-04-20  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/split_merge.h: remove the "protected" attribute for
	  'SM_var2_hardest_cut_off' for easier inclusion in fastjet. Note
	  however that the 'protected' declaration in the previous version
	  was used to prevent from dangerous usage of the variable. This
	  is still applicable now!

2007-04-18  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/area.cpp: Add a parameter '_hard_only' which allow to
	  compute only the hard jets area (without the purely ghosted
	  ones.

	* src/split_merge.h/cpp: Add a cut-off on the SM_var of the
	  hardest protojet. This is useful for computation of the area of
	  the hard jets without computing the purel ghosted ones. Note
	  that this cut-off is colinear-unsafe so has to be used with
	  great care.
	
2007-04-13  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/area.cpp: add Carea, the class to compute jet area

2007-03-16  Gregory Soyez  <g.soyez@ulg.ac.be>

	* SISCone 1.1.1 (tags/siscone-1.1.1)

2007-03-15  Gregory Soyez  <g.soyez@ulg.ac.be>

	* doc/html/usage.html: update the html doc for the recent
	  modifications of the split-merge algorithm.

	* src/split_merge.cpp: improve the recomputation method when two
	  jets are very close in the ordering when SM var is set to SM_Et

2007-03-15  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  modified fix to multiple-pass bug, in hope of being minimally
	  sensitive to rounding errors
	
2007-03-15  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/siscone.h: set the default number of passes to 0

	* examples/main.cpp: adding two command line parameters to the 
	  siscone application:
	  - npass controls the number of passes (0 by default)
	  - sm    controls the choice for the split--merge variable

2007-03-14  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/momentum.h: add Et (inline) member function

	* src/siscone.h: remove backward-compatibility computation members to
	  make things more clear.

	* src/split_merge.cpp: 
	  - fix multiple-pass bug
	  - add Et SM variable management

2007-03-14  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  put an assert for zero-size jets (common sign of a bug...);
	  ensured that "recomputed" protocones (with full momentum) also
	  have their eta-phi recalculated.

2007-03-12  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  added some more debugging output.
	
2007-03-10  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  fixed some typos and a bug in the EPSILON_SPLITMERGE case for
	  pt-tilde.

2007-03-09  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/siscone.h: The default value for the SM variable is set to
	  pttilde

	* src/split_merge.h/cpp: Update the split--merge procedure so that
	  it takes into account the choice for the split--merge
	  variable. Among the four choices, (pt_tilde, mt, pt and Et),
	  pt_tilde is the default (mt and pt can lead to IR unsafety). Et
	  is not yet implemented. We strongly advise to keep default value.
	
2007-03-09  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/siscone.h|cpp: 
	* src/split_merge.h|cpp: 
	  introduced an enum, Esplit_merge_scale (naming convention in
	  analogy with the leading "C" for classes), which contains values
	  SM_pt, SM_Et, SM_mt, SM_pttilde, and put in routines that take
	  the enum (as well as leaving in old ones)
	
2007-03-06  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  added transverse mass to info printed out about protojets with
	  the debug mode on (helpful in investigating limiting IR cases)

2007-03-02  Gregory Soyez  <g.soyez@ulg.ac.be>

	* SISCone 1.1.0 (tags/siscone-1.1.0)

2007-03-02  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  transformed a quiet error on illegal f values into a throw.

	* src/siscone.cpp: 
	  throw an error on illegal R values.

2007-03-01  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp|h:
	  added a new member variable, most_ambiguous_split, which records
	  the degree of ambiguity of the most ambiguous decision about
	  attributing a particle to one or other jet during a split step.
	  Useful for testing purposes.
	
2007-03-01  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/split_merge.cpp: set the full momentum
	  information on stable cones when we add them 
	  to the protojet list

	* src/siscone.h,cpp: add comments concerning the 
	  split_merge_on_transverse_mass parameter

	* src/defines.h (VERSION): set to 1.1.0beta

	* src/split_merge.cpp (siscone): 
	  - set ptmin as a real pt cut-off (independent on the 
	    choice of variable for the SM)
	  - code cleaned (involves other files e.g. defines.h 
	    momentum.h/cpp, siscone.h/cpp)

	* set the website to the HEPForge one in headers

	* replaced 'content' by 'contents' everywhere
	  WARNING: it implies Cjet::contents and 
	                      Csplit_merge::save_contents

	* src/quadtree.cpp (siscone): replace 'childs' with 'children'

	
2007-02-21  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/protocones.cpp (siscone): 
	  - remove all functions that are no longer necessary and replace
	    them by their new version. This includes the computatin of the
	    cone content, its re-computation, the check for co-circularity
	    and the test for stable cones in the co-circular situations.
	  - add a few comments of potentially tricky points.
	  - remove "cout" statements.
	  - remove 'largest_cocircular_range' which is no longer used

	* src/vicinity.h: 
	  - "largest_cocircular_range" removed.  
	  - quadtree related stuff removed. As a consequence,
	    'build_from_list' is renamed 'build'. The usage of the
	    quadtree can now only be used in
	    'Cstable_cone::proceed_with_stability' hence, the USE_QUADTREE
	    define has been renamed USE_QUADTREE_FOR_STABILITY_TEST.
	  - Comments aligned to make the code clearer.

	* src/momentum.h: Add mass() and mass2() member functions to
	  Cmomentum().
	  Put inline functions in the header rather than in the source 
	  file.

	* add C++ mark ("// -*- C++ -*-") in the headers where it was 
	  missing

2007-02-20  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  enhanced check on infinite rapidities to include also
	  meaningless rapidities.

	* src/split_merge.cpp|h: 
	* src/siscone.cpp: 
	  sorted out an issue on multi-pass runs caused by earlier fix for
	  transverse mass ordering.
	
2007-02-20 [am-pm] Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/split_merge.cpp: 
	  fixed a bug that appeared once split_merge_on_transverse_mass
	  got moved into the Csplit_merge_ptcomparison class

	* src/protocones.cpp|h: 
	  introduced compute_cone_contents_nodist(), which calculates the
	  initial cone contents by circulating around all in/out
	  operations and collecting the net result --- this avoids any
	  distance calculations and so removes a potential source of
	  rounding error. (Any remaining rounding error is dealt with by
	  cocircularity tests).

	* src/defines.h
	  added more info about the meaning of the different EPSILON
	  scales.
	
2007-02-19 [evening] Gavin Salam  <salam@lpthe.jussieu.fr>
	
	* src/defines.h: 
	  introduced const bool split_merge_on_transverse_mass, which
	  determines whether the split merge occurs on transverse mass
	  instead of pt -- the latter turns out to be IR unsafe in
	  mom-conserving events for moderately large values of R (R>1)
	
	* src/split_merge.cpp: 
	  implemented the split-merge ordering on transverse masses,
	  including the limit of there being small differences.
	
	* src/momentum.h: 
	  introduced perpmass2() which returns the transverse mass,
	  pt^2+m^2

	
2007-02-19 [pm] Gavin Salam  <salam@lpthe.jussieu.fr>

	NB: seg-faults are being seen sporadically when fastjet writes its
	description & need to be understood (but very rare and valgrind
	gives nothing on small numbers of events...)

	* src/defines.h: 
	  added optional #define EPSILON_SPLITMERGE, which if defined,
	  sets a threshold for pt differences below which the ordering is
	  determined from the explicit particle content...

	* src/split_merge.cpp|h: 
	  trying to introduce more "exact" pt comparison in split merge to
	  deal with multiple scales -- this involves a new
	  Csplit_merge_ptcomparison class which allows the set to carry
	  out comparisons while making use of knowledge about the particle
	  momenta inside the split_merge class.

	* src/circulator.h: 
	  added != and == comparison operators.

	* src/protocones.h|cpp: 
	  added Cstable_cones::test_cone_cocircular_p3() for carrying out
	  a p^3 check of stability -- NB seems a bit slower for small p,
	  but obviously much better for large p... Tests of 2*10^5
	  particles show no errors, longer tests to be done later...

2007-02-19 [am, early pm] Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/vicinity.h|cpp: 
	  introduced the Cvicinity_inclusion class to allow one to carry
	  out checks both on the inclusion in the cone and in its
	  "cocircular" border. Made corresponding changes elsewhere.
	
	* src/protocones.h|cpp: 
	  wrote new_cocircular_check() and ran a certain number of tests
	  on it; currently it is this one that is being called from
	  update_cone(), but it still uses the original 2^p routine for
	  actually checking the cone status.

	* src/[elsewhere]
	  added a lot of (now commented) debugging statements to help fix
	  bugs in the new_cocircular_check().
	
2007-02-18 [pm - later] Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/circulator.h:  *** ADDED ***
	  class for a circulator, used below.

	* src/protocones.(h|cpp): 
	  wrote prepare_cocircular_lists(), and checked that it's working
	  sensibly on some simple test events; also added code for
	  esetablishing the largest cocircular range among the children of
	  the current parent (should be used later to establish a more
	  reliable in/out status).

	  NB: the call to this function has added another 1-2% slowdown,
	  and we're now about 3-4% slower than before starting this
	  morning. But this should be the last of the changes that adds
	  significant extra time use?

	* src/vicinity.(h|cpp): 
	  support code for the protocones modification
	
2007-02-18 [pm]  Gavin Salam  <salam@lpthe.jussieu.fr>

	* src/defines.h: 
	  changed default EPSILON values to reflect what will be needed
	  with the new approach.
	
	* src/vicinity.cpp: 
	  carried out the calculation of cocircular_range inside the
	  append_to_vicinity member function; the extra
	  calculations/storage etc lead to a 2-3% slow-down for the
	  standard fastjet (354 particle) test event with R=1.

	* src/momentum.h: 
	  added a small 2-vector class, needed as a shorthand in
	  vicinity.cpp, plus various small utility routines.

	* src/vicinity.h: 
	  introduced cocircular_range and cocircular (list) as members of
	  Cvicinity_elm

	* src/momentum.h: 
	  introduced phi_in_range, dphi and abs_dphi inline functions.
	
2007-02-18 [am] Gavin Salam  <salam@lpthe.jussieu.fr> 

	* src/vicinity.cpp (include): 
	  switched to twopi from defines.h instead of the pi2 class member

	* src/siscone_error.(cpp|h):  *** ADDED ***
	  this is a simple class for throwing errors.

	* src/protocones.cpp: 
	  caused test_cone cocircular to throw errors when it receives
	  more than 32 points

	  carried out replacement client -> candidate

	* src/defines.h: 
	  introduced definition of twopi, which is used in many place (only
	  some usage instances have been replaced for now).


2007-02-16  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/defines.h: consider the limit on cocircularity and
	  collinearity as different ones. This introduces the
	  EPSILON_COCIRCULAR definition.

	* src/protocones.cpp (siscone): 
	  1. the list of cocircular situations already encountered is
	     maintained with a pair of references (the cone contents and
	     its border) instead of its coordinates.
	  2. we have improved the recomputation of the cone contents by
	     dynamically tracking he particles inside of the cone. This
	     adds a list of included particles in Cvicinity as well as a
	     pointer to elements of that list in vicinity elements.

2007-02-15  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/protocones.cpp: Code has been restructured to clearly
	  separate the cocircular case
	
	* dealt woth cocircularity and 2\pi periodicity and added 
	  an inline fction

2007-02-14  Gregory Soyez  <g.soyez@ulg.ac.be>

	* src/reference.cpp (siscone): ensures that the reference is not
	  zero

	* src/protocones.cpp (siscone): Fix a bug with the interference
	  between the recomputation of jets and the update of cocircular
	  points
	
	* src/protocones.cpp (siscone): add tests for recomputation of the
	  cone content for the case of cocircular points
	
	* src/protocones.cpp (siscone): when testing the threshold for
	  recomputation of te cone content, we add a test putting
	  automatically the cone to 0 when it is empty.

2007-02-13  Gregory Soyez  <g.soyez@ulg.ac.be>

	* We add a test of cocircularity: when more the p>2 particles are
	  found on the same circle, we branch to a different test of cone
	  stability. This new part of the algorithm tests all possible
	  inclusions/exclusions of the particles along the circle in a
	  2^p-type algorithm. Note that findling large values of p is
	  highly improbable !

2007-02-12  Gregory Soyez  <g.soyez@ulg.ac.be>

	* when traversing the centre list (in stable cones search), we
	  start with the centre which is the most separated from its
	  neighbours. This allows to minimize the possibility that we
	  miscomputed the computation of the initial cone content due to
	  possible rounding errors when two centres are too close.

2007-02-12  Gregory Soyez  <g.soyez@ulg.ac.be>

	* in collinear merging, take care of the periodicity in phi

	* put the threshold for collinear merging in defines.h
	  (EPSILON_COLLINEAR)
	
2007-02-12  Gregory Soyez  <g.soyez@ulg.ac.be>

	* undo the previous modification and use another approach to deal
	  with collinear particles: we keep the p_remain list as it was
	  before (see revision 84). Instead, after computing p_remain, we
	  compute p_uncol which is obtained from p_remain by merging
	  collinear particles. In the siscone main loop, we then use
	  p_uncol instead of p_remain for the search for stable
	  cones. Note that with this modification, the 'parent_index'
	  field of Cmomentum is back to its original definition as a
	  'int'.

2007-02-12  Gregory Soyez <g.soyez@ulg.ac.be>

	* remove initialisation of parent_index in momentum.cpp and
	  vicinity.cpp This is allowed because of the Npass loop in
	  siscone. Indeed, parent_index is only used internally in
	  split_merge and init at the very beginning of the loop by a call
	  to init_pleft 

	* replaced "int parent_index" by "vector<int> parent_index" and
	  align the code in split_merge.cpp

	* add a few lines off code in split_merge.cpp to account for
	  collinear particles.

	* Note concerning the previous update: the change has been
	  validated and is no longer considered as temporary

2007-02-12  Gregory Soyez <g.soyez@ulg.ac.be>

	* Changed the test for recomputation of cone content in Cstable_cones
	  see defines.h for details
	  (this change may be temporary)

2007-02-10  Gregory Soyez <g.soyez@ulg.ac.be>

	* fixed doxygen documentation issues:
	   - undocumented or renamed parameters
	   - include various links into a custom html footer
	
2007-01-25  Gregory Soyez <g.soyez@ulg.ac.be>

	* fixed memory leak for Cvicinity::ve_list 
	  in Cvicinity::set_particle_list()
	
2007-01-23  Gavin SALAM  <salam@lpthe.jussieu.fr>

	* added _ptmin argument to Csiscone::recompute_jets(...)

2007-01-22  Gregory Soyez <g.soyez@ulg.ac.be>

	* add ptmin threshold on protojets during split-merge
	* modify example program to allow for the --ptmin option

2007-01-20  Gregory Soyez <g.soyez@ulg.ac.be>

	* fix typo mistake in split_merge.cpp

2007-01-18  Gregory Soyez <g.soyez@ulg.ac.be>

	* insert a header on top of each source files to give brief information
	  about its content, the SISCone project and copyright
	
2007-01-03  Gregory Soyez <g.soyez@ulg.ac.be>

	* remove the usage of the quadtree in stable cones detection.
	  Usage of the quadtree in vicinity list creation and final stability
	  tests can be switched on buy defining USE_QUADTREE in defines.h.
	  This step was not fully achieved in the last update.

2006-12-28  Gregory Soyez <g.soyez@ulg.ac.be>
	
	* remove the usage of the quadtree in stable cones detection.
	  Usage of the quadtree in vicinity list creation and final stability
	  tests can be switched on by defining USE_QUADTREE in defines.h

2006-12-28  Gavin Salam  <salam@lpthe.jussieu.fr>

        * commented out various "template std::vector<...>" lines to solve
	  compilation problem on Macs.
	
	* modified the make depend targets so that they do not include 
	  "standard" include files (which differ from one system to
	  another). 

	* fixed log(_Np) bug pointed out by Matteo; fixed program name in
	  defines.h 

2006-12-28  Gregory Soyez <g.soyez@ulg.ac.be>

	* replace variables with name being "underscore" followed by
	  a single letter by longer names since they lead to compilation
	  problems under Mac. In practice, we renamed _N with _Np in hash.cpp/h
	  and _R by _radius in protocones.cpp/h and siscone.cpp/h
	
2006-12-27  Gregory Soyez <g.soyez@ulg.ac.be>

        * arranged for "make dist" to create a file with the same version
	  name in the directory and the tar file; made the tar-file
	  read-only (to avoid involuntarily overwrite); removed svn file
	  from the examples/events subdirectory.
	
2006-12-26  Gregory Soyez <g.soyez@ulg.ac.be>

	* updated the 'dist' target in the Makefile: include mem_check
	  with the correct path and build archive so that it unpacks into
	  a siscone-1.0-beta directory

	* fix typos in INSTALL

2006-12-26  Gavin Salam  <salam@lpthe.jussieu.fr>

        * Changed banner so that first char is # (to allow the rest of the
	  line to be considered a comment by things like gnuplot).	
	
	* moved scones -> siscone (and sorted out various "ignores")
	
	* Reordered changelog so that later stuff appears first (I think
	  this is standard? Makes it easier to see what's been happening
	  recently...)

	* Tidying up: moved jets.gri and mem_check into the examples
	  directory; added -f to "rm" command in make clean to avoid
	  errors; modified siscones->siscone in a couple of places in
	  doc.

	* Brought the README and INSTALL files up to date

	* set some svn:ignore property so as to ignore .dat files (to
	  reduce "noise" with svn status).

	* added #!/bin/bash to head of examples/mem_check
	
2006-12-22  Gregory Soyez <g.soyez@ulg.ac.be>

	* rename scones namespace into siscone

	* put ranlux stuff into the namespace (we don't want to
	  pollute the gobal namespace

	* add doc/devel as directory for developer's documentation
	  (using Doxygen)

	* scones.h/cpp is renamed siscone.h/cpp

	* creation of an 'examples' directory for various programs
	  only the library libsiscone.a is left in the src dir
	  Malefiles are modified accordingly


2006-12-21  Gavin Salam  <salam@lpthe.jussieu.fr>

	* added the MERGE_IDENTICAL_PROTOCONES_DEFAULT_TRUE define to
	  allow one to make MERGE_IDENTICAL_PROTOCONES to be set true by
	  default if need be. (This makes it a bit easier to make a quick
	  modification to run a test).

	* changed some of the related comments

        * replaced occurrences of "extensive" with "multipass"
	
	* Added the ChangeLog file!

	
2006-12-21 START OF CHANGELOG
	
