Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
This is an older version of Boost and was released in 2013. The current version is 1.90.0.
Unit of Least Precision or Unit in the Last Place is the gap between two different, but as close as possible, floating-point numbers.
Most decimal values, for example 0.1, cannot be exactly represented as floating-point values, but will be stored as the closest representable floating-point.
Functions are provided for finding adjacent greater and lesser floating-point values, and estimating the number of gaps between any two floating-point values.
The floating-point type FPT must have has a fixed number of bits in the representation. The number of bits may set at runtime, but must be the same for all numbers. For example, NTL::quad_float type (fixed 128-bit representation) or NTL::RR type (arbitrary but fixed decimal digits, default 150) but not a type that extends the representation to provide an exact representation for any number, for example XRC eXact Real in C.