This file contains the history of SISCone releases. For each one,
we give a short summary of the important changes from the previous
version. If you want to see a more detailed list of changes, please
read the ChangeLog file.

SISCone version 3.0.5 (April 24 2020)
=====================

* Minor release, fixed signed/unsigned warning in bitshift operations
  (version to be included in FastJet>=3.3.4)

SISCone version 3.0.4 (October 1 2018)
=====================

* Minor release, improved shared library handling by fixing
  inter-dependencies. (version to be included in FastJet>=3.3.2)

SISCone version 3.0.3 (August 3 2016)
=====================

* Minor release, installing config.h to include flags decided at
  configure time. (version to be included in FastJet>=3.2.1)

SISCone version 3.0.2 (March 16 2016)
=====================

* Minor release, fixing a bug due to an array being used uninitialised
  (no impact on results). Also replaced auto_ptr by unique_ptr when
  supported by compiler (version to be included in FastJet>=3.2.0)

SISCone version 3.0.1 (February 29 2016)
=====================

* Minor release, fixing a bug due to a rounding issue that occurs the
  theta range in (rare) specific configurations where theta=pi in the
  split-merge procedure for spherical SISCone

SISCone version 3.0.0 (September 9 2014)
=====================

* Added the option of running SISCone with progressive removal,
  corresponding to the following algorithm:

    1. search for stable cones
    2. declare the hardest stable cone a jet and remove its particles
       from the list of remaining particles
    3. if there are some remaining particles, go back to 1.

  Use Csiscone::compute_jets_progressive_removal(...) for this version
  of SISCone

  The scale used to determine which is the hardest stable cone can be
  chosen amongst the same options as the scale used for the
  split--merge step [SM_pttilde by default for the pp version of
  SISCone, SM_Etilde for the spherical version].  Alternatively, a
  user-defined scale choice can be provided using set_user_scale(...).

  Version to be included in FastJet>=3.1.0

SISCone version 2.0.6 (April 9 2013)
=====================
* Minor release fixing an issue concerning the installation of
  configuration headers and bringing small updates in the autotools
  build system (version to be included in FastJet>=3.0.4)

SISCone version 2.0.5 (January 17 2012)
=====================
* Minor release bringing minor improvements to the build system
  (version to be included in FastJet>=3.0.2)

SISCone version 2.0.4 (November 25 2011)
=====================
* Minor release to remove a few gcc warnings when compiled with
  high warning level (-ansi -pedantic -Wextra -Wshadow)
  (version to be included in FastJet>=3.0.1)

SISCone version 2.0.3 (October 5 2011)
=====================
* Minor release to fix a badly documented Etilde variable in the
  spherical version of SISCone and to remove a few gcc warnings
  (version to be included in FastJet 3.x)

SISCone version 2.0.2 (May 2011)
=====================
* minor modifications to the build system
  (version to be included in FastJet 3.x)

SISCone version 2.0.1 (May 2009)
=====================
* enabled shared libraries by default
  [that was the source of a bug in fastJet]
* replaced _R with _radius to fix build problems on old OSX systems 
* fixed some syntax inconsistencies in Makefile.am's


SISCone version 2.0.0 (Apr 2009)
=====================
* Added a spherical version of SISCone for use in e+e- collisions
  This typically works in the same way as the pp version of SISCone
  with the following remarks:
   - the classes fot the spherical versions of SISCone are prefixed by
     'CSph' instead of 'C' (e.g. CSphMomentum CSphSISCone)
   - the cone radius is defined as its half opening angle (particle
     distances are also defined through the angle they define, or,
     equivalently, as distances on the surface of a unit sphere)
   - For ordering the protojets during the split--merge, we use
     E_tilde defined as
                              /      |p_i X p_J|^2  \
	    \sum_{i\in J} E_i | 1 + --------------- |
	                      \      |p_i|^2 E_J^2  /
     Note that the computation of the overlap uses the "plain" energy

* Added a flag (Csiscone::use_pt_weighted_splitting) to modify the
  split part of the split-merge procedure in such a way that a shared
  particle i is assigned the one of the overlapping jets j=1,2 that
  has the smaller value of DeltaR_{ij}/p_{tj}. This produces more
  circular jets.

* fixed a bug in the computation of the rapidity range in the
  split-merge step

* the protocones list now contains the full 4-momentum information
  (rather than just eta and phi)

* fixed bugs in example/test.cpp


SISCone version 1.3.3 (Aug 2008)
=====================
* added bugfix for g++-4.3 (missing headers for "exit")


SISCone version 1.3.2 (Mar 2008)
=====================
* VERSION and PROGRAM (or PACKAGE_NAME) are no longer accessible
  directly because of potential conflicts with other packages. 
  You should use siscone_version() and siscone_package_name()
  instead. (Thanks to Rolf Seuster)
* allow the users to set their own default compilation flags.


SISCone version 1.3.1 (Mar 2008)
=====================
* fixed some compilation issues under windows


SISCone version 1.3.0 (Nov 2007)
=====================

* The main update in this new release is the switch to
  'autotools'. This means that instead of using the (static) Makefile
  build process, you can now use the "standard ./configure; make; make
  install" approach. See the INSTALL file for details.

* added a 'siscone_area' example of how jet areas work within SISCone.


SISCone version 1.2.0 (Jun 2007)
=====================

* 10-15% speed increase by introducing a tiling in the eta-phi plane
  allowing for better overlap checking in the split--merge. This can
  turn into a bigger effect for area computations.

* implementing a 'jet area' class to compute active and/or passive
  areas.

* in examples:
  - fix bug in the cmdline parsing (there was a segfault with
    unrecognised long options),
  - add "passes information" to the verbose output of the main siscone
    program,
  - solve problems with the 'time' example.


SISCone version 1.1.1 (Mar 2007)
=====================

* The major upgrade is the use of pttilde (p-scheme pt) instead
  of mt in the split--merge process. Indeed, we have noticed 
  that mt can lead to IR usafety in the case of two back-to-back 
  narrow-decay-width unstable particles (e.g. a pair of Higgs bosons).
  See http://projects.hepforge.org/siscone/sm_issue.html for details.

  Note that SISCone 1.1.1 allows the user to specify its choice for
  the split-merge variable (we highly recommand the default choice)

* The number of passes is now set to infinity (0) by default

* Small minor changes in the 'siscone' command-line options


SISCone version 1.1.0 (Mar 2007)
=====================

* dealt with colinearity issues

* dealt with cocircularity situations (and related rounding errors)

* use mt instead of pt in the split-merge 
  pt lead to some IR unsafety for events with momentum conservation

* move all references to HEPForge

* Important note: some typos have been fixed. As a consequence, some
  end-user members have been affected:
   - The contents of the jets is accessed through 'Cjet::contents'
     instead of 'Cjet::content'
   - The function called to save the jet contents to disk is 
     'Csplit_merge::save_contents' instead of 'Csplit_merge::save_content'
     Note that 'Csiscone::save_contents' is also valid.


SISCone version 1.0.0 (Jan 2007)
=====================

This is the first stable release of siscone. 
