diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/get-started.tex | 3 | ||||
| -rw-r--r-- | doc/what-is-libzahl.tex | 41 |
2 files changed, 36 insertions, 8 deletions
diff --git a/doc/get-started.tex b/doc/get-started.tex index 1596975..bbf62e0 100644 --- a/doc/get-started.tex +++ b/doc/get-started.tex @@ -8,6 +8,9 @@ You should read the sections in order. \minitoc +% TODO add a section a linking and stuff here. + + \newpage \section{Initialisation} \label{sec:Initialisation} diff --git a/doc/what-is-libzahl.tex b/doc/what-is-libzahl.tex index 0693437..0b76fd2 100644 --- a/doc/what-is-libzahl.tex +++ b/doc/what-is-libzahl.tex @@ -44,7 +44,7 @@ number types than integers. libzahl only supports integers. \label{sec:Why does it exist?} libzahl's main competitors are GNU MP (gmp),\footnote{GNU -Multiple Precision Arithmetic Library} LibTomMath (ltm), +Multiple Precision Arithmetic Library} LibTomMath (ltm), TomsFastMath (tfm) and Hebimath. All of these have problems: \begin{itemize} @@ -65,12 +65,6 @@ this, it is not really that simple. TomsFastMath is slow, complicated, and is not a true big integer library and is specifically targeted at cryptography. - -\item -Hebimath is far from stable, some fundamental functions -are not implemented and some functions are broken. The -author thinks Hebimath is promising, but that many things -can be done better. \end{itemize} libzahl is developed under the suckless.org umbrella. @@ -82,6 +76,18 @@ applications. Currently however, it does not support multithreading, but it has better support multiprocessing and distributed computing than its competitor. +Lesser ``competitors'' to libzahl include Hebimath and +bsdnt. + +\begin{itemize} +\item +Hebimath is far from stable, some fundamental functions +are not implemented and some functions are broken. The +author of libzahl thinks Hebimath is promising, but that +it could be better designed. Like libzahl, Hebimath aims +to follow the suckless philosophy. +\end{itemize} + \newpage \section{How is it different?} @@ -136,7 +142,26 @@ occur, not also after each function-return. Additionally, libzahl tries to keep the functions' names simple and natural rather than techniqual or mathematical. The names resemble those of the standard -integer operators. +integer operators. For example, the left-shift, right-shift +and truncation bit-operations in libzahl is called +{\tt zlsh}, {\tt zrsh} and {\tt ztrunc}, respectively. +In GNU MP, they are called {\tt mpz\_mul\_2exp}, +{\tt mpz\_tdiv\_q\_2exp} and {\tt mpz\_tdiv\_r\_2exp}. +The need of complicated names are diminished by resisting +to implement all possible variants of each operations. +Variants of a function simply append a short description +of the difference in plain text. For example, a variant of +{\tt zadd} that makes the assumption that both operands +are non-negative (or if not so, calculates the sum of +their absolute values) is called {\tt zadd\_unsigned}. +If libzahl would have had floored and ceiled variants of +{\tt zdiv} (truncated division), they would have been +called {\tt zdiv\_floor} and {\tt zdiv\_ceiling}. +{\tt zdiv} and {\tt zmod} (modulus) are variants of +{\tt zdivmod} that throw away one of the outputs. These +names can be compared to GNU MP's variants of truncated +division: {\tt mpz\_tdiv\_q}, {\tt mpz\_tdiv\_r} and +{\tt mpz\_tdiv\_qr}. \newpage |