\section{Reusable table styles and schemas}
\key{\gradtablestyle{name}{keys}} saves table appearance.

\key{\gradtableschema{name}{body}} saves column and header declarations.

Use style=name and \key{\graduseschema{name}}. Definitions may be placed in the
preamble. Redefinition replaces an earlier definition and follows TeX grouping.
\begin{demo}{Shared structure, different rule styles}
\gradtablestyle{benchmark}{rules=booktabs,header align=c,
  text width=30mm,graphic width=40mm,label width=12mm,
  row stretch=1.3,group color=gradbarsBlue!8}
\gradtableschema{benchmark}{
  \gradcolumn{method}{Method}
  \gradcolumn[type=bar,mark=both,
    options={max=100,precision=1}]{score}{Score}
}
\begin{center}
\begin{gradtable}[align=c,header align=c,style=benchmark]
  \graduseschema{benchmark}
  \gradgroup{Validation}
  \gradrow{A,81.5}
  \gradrow{B,88.2}
\end{gradtable}
\end{center}

\begin{center}
\begin{gradtable}[align=c,header align=c,style=benchmark,rules=grid]
  \graduseschema{benchmark}
  \gradgroup{Test}
  \gradrow{A,79.6}
  \gradrow{B,85.3}
\end{gradtable}
\end{center}
\end{demo}
Options after style override it. Styles may reference other styles and schemas
may compose schemas; cycles cause errors. Ids must remain unique. Apply schemas
before any data or group. Each table measures and ranks its own data separately.