fst_rand.hpp File Reference

FST4-owned pseudo-random number generator (UCRT-compatible LCG), replacing platform-specific std::rand()/std::srand(). More...

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Namespaces
namespace	FST
	The Feature Selection Toolbox 4 library: every library component – data access, criteria and classifiers, search algorithms, result trackers and the global infrastructure – lives in this namespace.

Functions
unsigned int &	FST::_fst_rand_state ()
	LCG state, one instance per thread; each thread starts from the default state 1.
void	FST::fst_srand (unsigned int seed)
	Seeds the calling thread's FST4 PRNG; use instead of std::srand().
int	FST::fst_rand ()
	Returns the next pseudo-random draw in 0..FST_RAND_MAX; use instead of std::rand().
unsigned long	FST::fst_rand_below (const unsigned long n)
	Returns a pseudo-random index in 0..n-1 (n >= 1); use instead of fst_rand()n.

Variables
const int	FST::FST_RAND_MAX = 32767
	Maximum value fst_rand() can return; use instead of the libc macro RAND_MAX.

Detailed Description

FST4-owned pseudo-random number generator (UCRT-compatible LCG), replacing platform-specific std::rand()/std::srand().

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Feature Selection Toolbox 4 source code

Author

Petr Somol (somol.nosp@m.@uti.nosp@m.a.cas.nosp@m..cz) with collaborators, see Contacts at https://fst.utia.cz

Version 4 was developed with Anthropic Claude models as coding assistants: Claude Fable 5 for the 2026 development (with minor contributions by Claude Opus 5), Claude Fable 5.1 for the pre-publication reviews of the full codebase, and Claude Opus 4.5 for the December 2025 audit of the FST3 codebase; design, decisions, review and acceptance are human work

Date

July 2026

Version

4.2.0

Note

FST4 was developed using MinGW-W64 g++ 15.2 and requires

• a C++17 conforming compiler and standard library (no Boost, unlike FST3),

• (optionally) LibSVM (http://www.csie.ntu.edu.tw/~cjlin/libsvm/, version 3.37; not distributed with FST4 — drop svm.cpp/svm.h into ./libsvm/, see libsvm/readme.txt)

Note that LibSVM is required for SVM related tools only. Ready-to-run SVM examples: demos/demo12t.cfg, demo23.cfg, demo25t.cfg and demo32t.cfg (configurations of the fst4 command-line tool).