2008-07-10 Naoaki Okazaki * libLBFGS 1.5: - Configurable starting index for L1-norm computation. A member variable lbfgs_parameter_t::orthantwise_start was added to specify the index number from which the library computes the L1 norm of the variables. - Fixed a zero-division error when the initial variables have already been a minimizer (reported by Takashi Imamichi). In this case, the library returns LBFGS_ALREADY_MINIMIZED status code. - Defined LBFGS_SUCCESS status code as zero; removed unused constants, LBFGSFALSE and LBFGSTRUE. - Fixed a compile error in an implicit down-cast. 2008-04-25 Naoaki Okazaki * libLBFGS 1.4: - Configurable line search algorithms. A member variable lbfgs_parameter_t::linesearch was added to choose either MoreThuente method (LBFGS_LINESEARCH_MORETHUENTE) or backtracking algorithm (LBFGS_LINESEARCH_BACKTRACKING). - Fixed a bug: the previous version did not compute psuedo-gradients properly in the line search routines for OW-LQN. This bug might quit an iteration process too early when the OW-LQN routine was activated (0 < lbfgs_parameter_t::orthantwise_c). - Configure script for POSIX environments. - SSE/SSE2 optimizations with GCC. - New functions lbfgs_malloc and lbfgs_free to use SSE/SSE2 routines transparently. It is uncessary to use these functions for libLBFGS built without SSE/SSE2 routines; you can still use any memory allocators if SSE/SSE2 routines are disabled in libLBFGS. 2007-12-16 Naoaki Okazaki * libLBFGS 1.3: - An API change. An argument was added to lbfgs() function to receive the final value of the objective function. This argument can be set to NULL if the final value is unnecessary. - Fixed a null-pointer bug in the sample code (reported by Takashi Imamichi). - Added build scripts for Microsoft Visual Studio 2005 and GCC. - Added README file. 2007-12-13 Naoaki Okazaki * libLBFGS 1.2: - Fixed a serious bug in orthant-wise L-BFGS. An important variable was used without initialization. - Configurable L-BFGS parameters (number of limited memories, epsilon). 2007-12-01 Naoaki Okazaki * libLBFGS 1.1: - Implemented orthant-wise L-BFGS. - Implemented lbfgs_parameter_init() function. - Fixed several bugs. - API documentation. 2007-09-20 Naoaki Okazaki * libLBFGS 1.0 - Initial release.