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Delay

In the delay function retrieves the previous value of a variable $X$. In the evaluation of Fib objects some branches will be evalued several times (e. g. for each value of an area element). The delay function will return the value, that it has taken before $UF_1$ calls of the delay function.


Status: not implemented, planned for implementation


Syntax: $UF=delay( X, UF_1, UF_2 )$


Description of the elements:

The dalay function stores for every call $a$ of an evaluation the value $W_a$, of the variable $X$. When the dalay function is called the $n$'th time, it returns the value $W_{n-UF_1}$, which the variable $X$ had in the $n-UF_1$ call. If $n-UF_1$ is smaler as $1$, the value of the subfunction $UF_2$ will be returned.

An run is determined by the evaluation of the entire Fib object. For example, the evaluation of the Fib object over the top most root-element is a run. If such an evaluation over the top root-element is restarted, a new run is started and the delay function discards all previous values $W_a$.


Example:


Note: With the delay function in connection with the set element, as well as area and function elements, for example, polygons can be easily generated. With the set-element, the edges of the polygon should be established. With the delay function the values for previous vertices are retrieved, which are then connected via divisional and functional elements.


next up previous contents index
Next: if Up: Real subfunctions Previous: Round   Contents   Index
Betti Österholz 2013-02-13