% here come various phrases which repeat throughout the reference
% section:

\newcommand{\eArgNumber}{The argument must be a number.}

% here are the actual command references:

\newcommand{\rAbs}{\vCommand{abs}
{Return the absolute value of the argument}
{x= abs(y)}
{Serves to determine the absolute value of its argument \Co{y}. \eArgNumber}
\vCommend{\sbref{sgn}}}

\newcommand{\rSgn}{\vCommand{sgn}
{Returns the sign of its argument}
{x= sgn(y)}
{Return value is
\[\text{\co{sgn(y)}}= 
\begin{cases} -1 & \text{if } y<0 \\
0 & \text{if } y=0 \\
1 & \text{if } y>0
\end{cases}\] \eArgNumber}
\vCommend{\Cref{noteOnTypes}, \sbref{abs}}}


