Initialization of clocked variables in algorithms.

chapters/statements.tex

@@ -35,6 +35,8 @@ \subsection{An Algorithm in a Model}\label{execution-of-an-algorithm-in-a-model}
   A continuous-time variable is initialized with the value of its \lstinline!start!-attribute.
 \item
   A discrete-time variable \lstinline!v! is initialized with \lstinline!pre(v)!.
+\item
+  A clocked variable \lstinline!v! in a discrete-time sub-partition, \cref{clocked-and-discretized-partition}, is initialized with \lstinline!previous(v)!.
 \item
   If at least one element of an array appears on the left hand side of the assignment operator, then the complete array is initialized in this algorithm section.
 \item
@@ -45,6 +47,8 @@ \subsection{An Algorithm in a Model}\label{execution-of-an-algorithm-in-a-model}
 Initialization is performed, in order that an algorithm section cannot introduce a ``memory'' (except in the case of discrete-time variables assigned in the algorithm), which could invalidate the assumptions of a numerical integration algorithm.
 Note, a Modelica tool may change the evaluation of an algorithm section, provided the result is identical to the case, as if the above conceptual processing is performed.
 
+For a clocked variables it is important to skip this initialization when not needed, in order to avoid an excessive amount of clocked states, \cref{clocked-state-variables}.
+
 An algorithm section is treated as an atomic vector-equation, which is sorted together with all other equations.
 For the sorting process (BLT), every algorithm section with N different left-hand side variables, is treated as an atomic N-dimensional vector-equation containing all variables appearing in the algorithm section.
 This guarantees that all N equations end up in an algebraic loop and the statements of the algorithm section remain together.