10進数と2進数の変換表をtexで作りたい．
2進数は4桁
符号付きは2の補数表現
test.tex

\documentclass[a4paper]{jsarticle}

\usepackage{pgf}    % pgfmath
\usepackage{pgffor} % foreach

\usepackage{multicol}


\begin{document}

\newcommand{\DtoB}[2][4]{% decimal to binary, unsigned
  \pgfmathsetbasenumberlength{#1}% 4-digit default 
  \pgfmathbin{#2}\pgfmathresult%
}

\newcommand{\BtoD}[1]{% binary to decimal, unsigned
  \pgfmathsetbasenumberlength{1}%
  \pgfmathparse{0b#1}\pgfmathresult%
}

\newcommand{\DtoCB}[1]{% signed decimal to 4-digit binary 
\ifnum #1 = 0%
  \pgfmathsetbasenumberlength{4}%
  \pgfmathbin{#1}\pgfmathresult%
\else%
  \ifnum #1 > 0%
    \pgfmathsetbasenumberlength{4}%
    \pgfmathbin{#1}\pgfmathresult%
  \else% #1 < 0
    \pgfmathsetbasenumberlength{3}%
    \pgfmathbin{8 + #1}1\pgfmathresult%
  \fi%
\fi%
}

\newcommand{\CBtoD}[1]{% 4-digit binary to sgiend decimal -8, -7, ..., 6, 7
  \pgfmathsetbasenumberlength{1}%
  \pgfmathparse{0b#1}%
  \ifnum \pgfmathresult > 7%
    \pgfmathparse{-8 - (8 - 0b#1)}%
    \pgfkeys{/pgf/number format/.cd,int trunc}%
    \pgfmathprintnumber{\pgfmathresult}% convert -1.0 --> -1
  \else%
    \pgfmathparse{0b#1}\pgfmathresult%
  \fi%
}



\def\DtoBloop#1{%
  \foreach \x in {#1}{$(\x)_{10} = (\DtoB{\x})_2$\\}%
}

\def\DtoCBloop#1{%
  \foreach \x in {#1}{$(\x)_{10} = (\DtoCB{\x})_2$\\}%
}

\def\BtoDloop#1{%
  \foreach \x in {#1}{$(\BtoD{\x})_{10} = (\x)_2$\\}%
}

\def\CBtoDloop#1{%
  \foreach \x in {#1}{$(\CBtoD{\x})_{10} = (\x)_2$\\}%
}

\begin{multicols*}{4}

\noindent
\DtoBloop{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}
\columnbreak

\noindent
\DtoCBloop{-8,-7,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7}
\columnbreak

\noindent
\CBtoDloop{0000,0001,0010,0011,0100,0101,0110,0111,1000,1001,1010,1011,1100,1101,1110,1111}
\columnbreak

\noindent
\BtoDloop{0000,0001,0010,0011,0100,0101,0110,0111,1000,1001,1010,1011,1100,1101,1110,1111}

\end{multicols*}

\end{document}
こうなります．