BasedOnFeedback

chapters/classes.tex

@@ -384,13 +384,13 @@ \subsection{Component Variability Prefixes discrete, parameter, constant}\label{
 
 \begin{nonnormative}
 For \lstinline!Real! variables we can distinguish two subtly different categories: discrete-time and piecewise constant, where the discrete-time variables are a subset of all piecewise constant variables.
+The \lstinline!Real! variables declared with the prefix \lstinline!discrete! is a subset of the discrete-time \lstinline!Real! variables.
 For a \lstinline!Real! variable, being discrete-time is equivalent to being assigned in a when-clause.
 A variable used as argument to \lstinline!pre! outside a when-clause must be discrete-time.
-The discrete-time variables are a subset of all variables that are piecewise constant and only change at events.
 Tools may optimize code to only compute piecewise constant variables at events.
 
 \begin{lstlisting}[language=modelica]
-model ShowDiscrete
+model PiecewiseConstantReals
   discrete Real xd1 "Must be assigned in a when-clause, discrete-time";
   Real xd2 "Assigned in a when-clause (below) and thus discrete-time";
   Real xc3 "Not discrete-time, but piecewise constant";
@@ -402,7 +402,7 @@ \subsection{Component Variability Prefixes discrete, parameter, constant}\label{
   // It is legal to use pre for a discrete-time variable outside of when
   xc3 = xd1 + pre(xd2);
   // But pre(xc3) would not be legal
-end ShowDiscrete;
+end PiecewiseConstantReals;
 \end{lstlisting}
 
 A \lstinline!parameter! variable is constant during simulation.  This prefix gives the library designer the possibility to express that the physical equations in a library are only valid if some of the used components are constant during simulation.  The same also holds for discrete-time and constant variables.  Additionally, the \lstinline!parameter! prefix allows a convenient graphical user interface in an experiment environment, to support quick changes of the most important constants of a compiled model.  In combination with an if-clause, a \lstinline!parameter! prefix allows removing parts of a model before the symbolic processing of a model takes place in order to avoid variable causalities in the model (similar to \lstinline!#ifdef! in C).  Class parameters can be sometimes used as an alternative.