SIMSCRIPT II.5 Programming Language

Discrete Simulation Concepts
ent classes, on their break ties attributes, if these are specified, or on a first-in, first-out basis if
no break ties attributes have been specified.
Table 5-2. Time Conversion Functions
Name
Argument
Function
Mode
Function
Values
Examples
weekday.f
REAL time
expression
integer 1 - 7
day of current week
weekday.f(5.32)
= 6
hour.f
REAL time
expression
integer 0 - 23
hour of current day
hour.f(5.32) = 7
minute.f
REAL time
expression
integer 0 - 59
minute of current
hour
minute.f(5.32)
= 40
Corresponding to the schedule statement is a cancel statement, which removes a specified process
or event notice from its future events set, before it has been selected for execution. This negates
the action of the schedule statement that filed the event notice. It is written:
cancel this process/event
and
cancel this event called variable
As usual, the first form is interpreted as:
cancel this event called event
The words the or the above can be substituted for this when necessary. The event notice removed
is not automatically destroyed. If required, it may be explicitly destroyed, as may any temporary
entity. An attempt to cancel an event that has not been scheduled, and is therefore not filed
in the future event set, terminates the program with an error message.
5.3.2 Assigning Event and Process Attributes
If an event or process notice is declared to have user-defined attributes, values may be assigned to
these in two ways: through standard attribute (entity) references in assignment statements, and also
within a schedule statement specifying the notice. Recall that a statement such as:
schedule an event given expression list at time expression
uses the time expression to set time.a(event) attribute. It will also assign the values given in
the expression list to successive attributes of the event notice, starting with the first user-defined
attribute. If fewer expressions are listed than there are attributes, the remaining attributes are ini-
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