Anylogic Variable Not Updating

Question

I an using a discrete event simulator in AnyLogic. I am having an issue with some code which updates a variable in my simulation. I store both the datetime at which the agent leaves the source block and the datetime at which it enters the sink block. I am trying to record the number of "rule breaks" for all agents. The rule break is defined below (two ways to break):

1) If the agent is received before a certain time (called SDC) and the agent is not completed by 5pm the same day, then the agent has broken the rule

2) If the agent is not completed by the next day at a certain time (called NDC), then the agent has broken the rule

I record a zero or a one for each agent if they break either rule in the variable called RuleBreak. However, in my simulation runs, the variable does not update at all. I hope I am just missing something small. Would appreciate any help! (code below)

Calendar received = Calendar.getInstance();
received.setTime(ReceivedDate);

Calendar completion = Calendar.getInstance();
completion.setTime(Completion);

Calendar SD_at_5 = Calendar.getInstance();
SD_at_5.setTime(ReceivedDate);
SD_at_5.set(Calendar.HOUR_OF_DAY,17);
SD_at_5.set(Calendar.MINUTE, 0);
SD_at_5.set(Calendar.SECOND, 0);

Calendar Tomorrow_at_NDC = Calendar.getInstance();
Tomorrow_at_NDC.setTime(ReceivedDate);
if(Tomorrow_at_NDC.get(Calendar.DAY_OF_WEEK) == 6)
    Tomorrow_at_NDC.add(Calendar.DATE, 3);
else 
    Tomorrow_at_NDC.add(Calendar.DATE, 1);
Tomorrow_at_NDC.add(Calendar.DATE, 1);
Tomorrow_at_NDC.set(Calendar.HOUR_OF_DAY,NDC);
Tomorrow_at_NDC.set(Calendar.MINUTE, 0);
Tomorrow_at_NDC.set(Calendar.SECOND, 0);

int Either_rule_break = 0;
double time_diff_SDC = differenceInCalendarUnits(TimeUnits.SECOND,completion.getTime(),SD_at_5.getTime());
double time_diff_NDC = differenceInCalendarUnits(TimeUnits.SECOND,completion.getTime(),Tomorrow_at_NDC.getTime());

if((received.get(Calendar.HOUR_OF_DAY) < SDC) && (time_diff_SDC <= 0))  
    Either_rule_break = Either_rule_break + 1;
else
   Either_rule_break = Either_rule_break + 0;

if((received.get(Calendar.HOUR_OF_DAY) >= SDC) && (time_diff_NDC <= 0))
    Either_rule_break = Either_rule_break + 1;
else
    Either_rule_break = Either_rule_break + 0;

if((Either_rule_break >= 1))
    RuleBreak = RuleBreak + 1;
else 
    RuleBreak = RuleBreak + 0;

Answer 1

You haven't really explained where this code is used and what it receives. I assume the code is in a function, called in the sink's on-enter action, where ReceivedDate and Completion are Date instances stored per agent (source exit time and sink entry time, as dates, captured via AnyLogic's date() function).

And looks like your SDC hour-of-day is stored in SDC and your NDC hour-of-day in NDC (with RuleBreak being a variable in Main or similar storing the total number of rule-breaks).

Your calculations look OK except that the Tomorrow_at_NDC Calendar calculation seems wrong: you add 1 day twice (if not Saturday) or 3 days plus 1 day (if Saturday; in a Java Calendar, day-of-week 1 is Monday).

(Your Java is also very 'inefficient' with unnecessary extra local variables and performing logic when you don't need to; eg, no point doing all the calendar preparation and check for your type 1 rule-break if the receive time is after the SDC hour.)

But are you sure there are any rule-breaks; how have you set up your model to ensure that there are (to test it)? Plus is RuleBreak definitely a variable outside of the agents that flow through your DES (ie, in Main or similar)? Plus are Completion and ReceivedDate definitely stored per agent so, for example, if your function was called checkForRuleBreaks you would be doing something like the below in your sink on-exit action:

agent.Completion = date();   // Agent received date set earlier in Source action
checkForRuleBreaks(agent.ReceivedDate, agent.Completion);

(In fact, you don't need to store the completion date in the agent at all since that will always be the current sim-date inside your function and so you can just calculate it there.)