JPS6336358A - Event scheduling system - Google Patents

Abstract

PURPOSE:To attain repetition of an event and to contrive to improve efficiency of work by updating the counter of events every time an event is terminated, and resetting the values of time parameter of an event and time parameter of each sub-event. CONSTITUTION:A time parameter consisting of a starting time variable and a terminating time variable, a counter that records number of times of repetition and a list in which an event to be a constituent element of the event are set to an event. Every time an event is terminated once, the counter is updated, the time parameter of the event and the time parameter of each sub-event are reset. Thereby, an operator can set repetition of an event briefly without providing setting of events and setting of time relation for the number of times of repetition, and efficiency of work and efficiency of utilization of resources such as storing areas etc. are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a scheduling method for arbitrary events on a computer, such as events in computer simulation and operations in computer animation.

(Prior art) Here, the event called is an arbitrary event on a computer,
In particular, in computer simulations, events that occur at a certain time or the behavior of objects are considered.

It is assumed that an event starts at a certain time (start time) and ends at a certain time (end time), and the time relationship between multiple events is set by the sequential relationship between their start time and end time. If an event starts at a certain time t1, the start time of each event may be set to tl. Also, event A is event B
If the start time of event A is started later than the start time of event B, the start time of event A may be set to a value later than the start time of event B. Also,
By setting a qualitative magnitude relationship between the start time or end time of each event, the start time of an event can be determined from the time relationship with other events without having to clearly set the start time of the event. It was also possible to do so.

For example, use the predicate hold to set the event event to start executing at time time, and set h
old(event, time) Furthermore, a predicate was provided to express the time relationship between events, and a schedule was set using this predicate. For example, the fact that event A occurs before event B is expressed as follows using the predicate before.

before (A, B) For details, see Mizoguchi et al., "Prototype production of an action planning system including r time information" (Information Processing Society of Japan 32nd (first half of 1985) National Conference proceedings pp, 1559-1560).

(Problem to be solved by the invention) However, although the above method can set the time order relationship between events, it is not possible to simply set the occurrence of a certain event repeatedly. There was a problem. For example, if we consider a case where a certain event A is repeated N times, we can write the start of event A N times using the predicate hold, or we can use the predicate seq to indicate that event B starts immediately after the end of event A, and write 5eq( A.

One possible method is to repeatedly set A). However, in the case of the former method, it is not possible to accurately know the time required from the start to the end of the execution of event A in boat fishing, so there is a limit to the descriptive ability of the predicate hold, which requires a clear start time. . Further, in both methods, the predicate hold or seq must be repeatedly set N times, and if the number N of iterations is large, it becomes very inefficient. Furthermore, in both methods, there are a plurality of time settings (N or N-1) regarding event A, resulting in a logical contradiction.

In order to avoid this contradiction, it is possible to prepare N events of exactly the same type as event A, but this results in duplicate event descriptions and requires a storage area to store the events, which is extremely inefficient. It is true.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an event with a time parameter consisting of a start time variable and an end time variable, a counter that records a repetition function, and a list that registers child events that are components of the event. The repetition of the event is realized by setting the above event, updating the counter of the above event every time the above event ends, and resetting the value of the time parameter of the above event and the time parameter of each child event of the above event. The purpose is to provide an event scheduling method that can

(Means for Solving the Problems) The event scheduling method of the present invention includes a time parameter consisting of a start time variable and an end time variable, a counter for recording the number of repetitions, and a child event that is a component of the event. The present invention is characterized in that a list for registering is set, the counter is updated each time the event ends, and the value of the time parameter of the event and the time parameter of each child event of the event is reset.

(Operation) In the present invention, an event includes a time parameter consisting of a start time variable and an end time variable, a counter that records the number of repetitions, a list containing names of child events that are constituent elements of the event, and a wait time at a time of interest. It has a list of child events inside and a list of child events being executed. The schedule of child events of the event is described in relative time from the event. When the event starts executing, the schedule of each child event is converted to an absolute time, the execution judgment of each child event is made, and the child events registered in the waiting child event list are executed. The exponent child event is moved from the waiting child event list to the executing child event list and executed. Each time an event ends, the above counter is updated, all of the above child events are returned to the waiting child event list, and the time parameters of the event and the time parameters of each of the above child events are updated after the end time of the event. and restart the execution of the event. The above process is repeated for the number of iterations. Note that if the events are hierarchically structured, the above process may be performed recursively for each child event.

(Example) An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a conceptual diagram showing an example of the time relationship of occurrence of events. The start time and completion time of each event are shown on the time axis. In this figure, event A starts at time t1 and time t
Ends in 2. Event B starts at time t2 and ends at time t3. Also, event A has its child events Al, A2.
A3, and the child event A1 is the start time t1 of event A.
starts at relative time tll with reference to
Ends in 3. Child event A2. The same applies to A3.

Note that it is shown that child events A1 and A2 start at the same time tll, and child events A1 and A3 end at the same time t13. Here, each time tl, t2. t3. tl
l, t12. The value of t13 may be undetermined.

Therefore, for example, if time t2 is undetermined, then FIG. 2 expresses the qualitative property that event B starts at the same time as event A ends.

FIG. 3 is a conceptual diagram showing an example of the time relationship between repeated events. Assume that event A is the same as in FIG. 2 and is repeated N times. The first execution of event A starts at time t1 and ends at time t2. Child event AI of event A, A2
．． A3 is relative time t11°t1 with respect to time t1
2. The start time and end time are determined by t13. The second execution of event A starts immediately after time t2 (in the case of discrete times, it will be time t2+1), and at time t
Ends in 3. Child event Al, A2. A3 is time t2
Relative time tll, t12. The start time and end time are determined by t13. tll, t
12. Since t13 is a relative time seen from event A,
The same value may be used in the first and second execution of event A. When actually executing the child event, tll, t12
．． t13 is converted to an absolute time based on the start time of event A. Thereafter, event A is repeated N times in the same manner. Third
In the figure, only one event A is repeated, but it is also possible for a plurality of different events to be repeated in parallel. Of course, non-repeating events may exist in parallel.

FIG. 4 is an explanatory diagram for representing the contents of the event. The contents of the event include the name, the execution body representing the execution content of the event, the name of the parent event that includes the event as a child event, the start time variable name,
It consists of an end time variable name, a repeat count counter, an end flag, a list of names of child events, a list of names of child events being executed, and a list of names of waiting child events. The name of an event can be any unique name that can be distinguished from other events, but it is convenient to use a path salt that includes the names of the parent event and all of the parent events above it. The execution body stores the content to be executed by the event. In Figure 4, as an example, hel
The execution content of printing the character "low" is stored. Although the name of the parent event is not necessarily required, it is convenient for implementing this method.

The start time variable name is a pointer to a storage area for storing the start time, and the value of the start time variable is either directly given by the user or determined by a time synchronization mechanism described later. The end time variable name is a pointer to a storage area for storing the end time. The value of the end time variable is determined in the same way as the start time variable. These two frequencies are collectively called the time parameter, and the event schedule is set by this time parameter. However, the value of the time parameter is not necessarily determined in advance, and may be dynamically determined based on the time relationship with other events.

The details will be described later. The repetition counter is for recording the number of repetitions of an event. The number of repetitions can be counted in any way, but if you give the number of repetitions to a counter when setting an event, and the value of the counter is decremented by one each time the event is completed, the number of repetitions will be completed. Since it is possible to know what has been done by seeing the value of the counter become 1, processing becomes easier. For events that do not repeat, the value of the repetition counter is 1 in advance. Furthermore, if it is desired to repeat the process an infinite number of times, a flag indicating infinite times (for example, 0) may be given to the repetition counter. however,
If the end time variable has a definite value and the current time is past the value of the end time variable, the event ends regardless of the value of the repetition counter. The completion flag is to indicate that the event has served its purpose during execution. The end flag is activated by the event itself when the gold event of the event ends and the processing of the execution body ends. When the end flag is activated, the event is ended, and the current time is stored in the end time variable. The child event name list is a list of all child event names included as constituent elements of the event. The list of names of child events that are being executed is a list of all the names of child events that have already started at the time of interest and have not yet ended.

Events are classified into standby events and execution events based on their status.

A standby event is one that has not yet occurred at the time T of interest and is in a state of waiting to start. An execution event is one that is already being executed at time T. Waiting events are registered in the waiting event list, and execution events are registered in the execution event list. In the initial state of scheduling (time 0 or any reference time), all events are first registered in the waiting event list.

Furthermore, when an event is actually caused by a device such as a computer according to the time relationship shown in FIG. 2.3, the time axis becomes discrete, and time is counted every certain unit time.

FIG. 1 is a block diagram showing the entire event scheduling system as an embodiment of the present invention. Event storage means 1 for storing and referencing the contents of events; event execution determination means 2 for determining whether the event of interest will be executed or finished at a certain time; A time synchronization means 3 for synchronization, an event repetition control means 4 for controlling repetition of an event, an event execution means 5 for executing the main body of the event, and a clock generation means 6 for giving a time are provided. ing. A connection line 7 for inputting the contents of an event into the event storage means 1; a connection line 8 for transmitting the contents of the event stored in the event storage means 1 to the event execution determination means 2; A connection line 9 for transmitting state transition information of execution or standby of the event to the event storage means 1, values of time parameters (start time variable and end time variable) in the event execution determination means 2, and the time at that time. A connection line 10 for transmitting time synchronization information consisting of A connection line 12 for transmitting the event that occurred and the time at that time to the event repetition control means 4, and a connection line 12 for transmitting to the event repetition control means 4 the event that was completed by synchronization with other events in the time synchronization means 3 and the time at that time. A connection line 13 for transmitting a time parameter for resetting the time parameter in the event repetition control means 4 to the event synchronization means 3, a connection line 14 for transmitting a time parameter to the event synchronization means 3, which is a completed child event of an event to be repeated. a connection line 15 for transmitting information for returning for repetition from the event repetition control means 4 to the event storage means; and an event execution determination means 2.
a connection line 16 for transmitting information as to whether or not to execute the event determined by and the time at which the event is executed to the event execution means 5;
Connection line 17 for outputting the execution result of the event execution means 5
, a connection line 18 is provided for transmitting the time generated by the clock generation means 5 to the event execution determination means 2.

The contents of the event shown in FIG. 4 are stored in the event storage means 1 shown in FIG. At the time of storage, a table for event reference is generated by combining the event base and the address of the storage area where the event contents are stored.

FIG. 5 is a flowchart showing an event scheduling system as an embodiment of the present invention. Processing is shown. A method of scheduling a certain event X at a certain time T will be described below as an example.

In step 101, it is determined from the value of the time parameter of event X and time T whether event X is executed at time T. If event X starts exactly at time T, synchronization with other events is performed based on the start time variable of event X and time T. Details will be described later. If it is determined in step 101 that the process should be executed, the process proceeds to step 102 to proceed to steps 103, 104, and 105, which indicate that the process should not be executed. If it is determined not to execute, step 106
Processing will proceed. If event X does not have any child events in step 103, the main body of event X is executed in step 104. If event X has a child event, step 105
Scheduling is performed for each of its child events. Scheduling of each child event is also performed in the same way as the process shown in FIG. In other words, the process is recursive. At this time, the schedule of each child event is converted into an absolute time by adding the value of the start time variable of event X to the start time variable and end time variable of each child event. What should be noted here is that the value of the time parameter of each child event (the relative value of event X) is not necessarily fixed. Therefore,
The value of the time parameter of each child event is dynamically determined by propagation of the value in a time-related network, which will be described later. Finally, in step 106, it is determined whether event X ends at time T. If it ends, event
Synchronization with other events is performed based on the end time variable and time T. Furthermore, if the event to be terminated is an event that should be repeated, the repetition control is performed. Details will be described later. In addition, step 1
The order of scheduling for each child event in step 03 and the execution of the main body in step 104 may be reversed.

The above explanation is based on a certain event X at a certain time T.
However, if a certain time [T1.
T2], the process shown in FIG. 1 may be repeated for each event at each time T while advancing time T by one unit time from time T1 to time T2. However, there is no need to perform a start check for events registered in the execution event list.

FIG. 6 is a flowchart for explaining step 101 of the start check in FIG. 5 in detail. Consider time T. First, in step 21, it is checked whether the value of the start time variable ts of event X is already determined or undetermined. To indicate that it is undetermined, an undetermined flag may be given to ts. If it is undetermined, it is assumed that event X will not be executed at time T, and event X will remain registered in the waiting event list. If ts is determined, step 2
2, the value of ts and time T are compared in magnitude. ts
If the value of is greater than time T, it is assumed that event X has not yet started at time T, and remains registered in the waiting event list. If the value of ts is less than or equal to time T, it is interpreted as being executed. At this time, if it is determined in step 23 that the value of ts is equal to time T, it is assumed that the event X starts exactly at time T, and in step 24 ts
Based on the time T, time synchronization with other events is performed.

A method for synchronizing will be described later. Events interpreted in step 22 to be executed are moved in step 25 from the waiting event list to the execution event list.

FIG. 7 is a flowchart illustrating in detail step 106 of the end check in FIG. Consider time T. First, in step 301, the end time variable te of the event
Check whether it is undetermined or determined (this is done in the same way as the start check). If te is determined, the value of te and time T are compared in step 302, and te and T are determined.
If it is below, time synchronization with other events is established based on te and time T in step 305. te
If is undetermined or te>T, it is checked in step 303 whether the end flag of event X is on. The end flag is activated by the event itself when the Kaneko event of the event ends (that is, the waiting child event list and the running child event list become empty) and the processing of the execution tree ends. be converted into If the end flag is not on, it is assumed that event X will not end at this time, and the end check process ends. If the end flag is on, it is checked in step 304 whether the value of the repetition counter t1 is 1. If a predetermined number of repetitions has been completed or the event does not originally repeat, the number of repetitions is 1. If the value of the iteration counter is 1,
Assuming that event X ends at time T, in step 305, set the value of end time variable te of event For example, the value of the repetition counter may be set to 0 in advance. Step 3
As can be seen from the processing from 01 to 304, even if the value of the repetition counter is other than 1, it is possible to prematurely end the repetition of event X depending on the value of the end time variable.

If it is determined at step 302 or step 304 that the event has ended, event X is removed from the running event list and the waiting event list at step 306. If the value of the iteration counter is greater than 1, step 308.309
．． Processing for iteration is done at 310. first,
In step 308, the value of the repetition counter of event X is decremented by 1, and the value of the start time variable ts of event X is given the value obtained by adding 1 to the current time T. Next, in step 309, all child events of event X are re-registered in the waiting child event list and returned to the initial state. If a child event (say Xi) of event X has further child events, the child events of child event X1 are returned to the waiting core child event list of child event X1. This filling is performed in the same way for all descendant events of event X. Next, in step 310, the time parameters of all child events of event X are reset. To do this, event X out of the time parameters of each child event
The value of the relative time explicitly set (set by the predicate occur, which will be described later) is converted into an absolute time based on the value of the start time variable ts of the event X.

If child event X1 of event X has further child events, first convert the start time variable of child event Convert to absolute time. Similar processing is performed for all descendant events of event X. To determine the time parameters of a child event based on the start time variable of its parent event, a time synchronization method, which will be described later, is used. Through the above processing, all descendant events of event X are returned to their initial state and are ready for the next iteration.

As described above, by the process explained based on Fig. 5.6.7,
Time synchronization and repetition in an arbitrary hierarchy of a plurality of different events forming a hierarchical structure is realized.

Next, a method of setting time relationships between events will be explained.

An example of a method for setting time relationships between events is shown in FIG. 8(a). When setting the time relationship, specify the setting time axis indicating whether it is an absolute time or a relative time from a certain event. When setting the time relationship of a child event in the definition of the content of a parent event, it is convenient to make the setting time axis a relative time viewed from the parent event. In Figure 8(a),
The time relationship of events shown in FIG. 2 is taken as an example. The fact that event A starts at absolute time t1 is expressed using the predicate occur with absolute time as the set time axis. Among events A, event A1 is relative time 3 (tl-tl in Figure 3).
The time axis is based on the start time of event A, and is expressed using the predicate occur. The predicate 5tart means that event A1 and event A2 start at the same time, and the predicate finish means that event A1 and event A3 end at the same time, and event A3 starts immediately after event A2.
The predicate seq expresses that . Furthermore, the fact that event A is repeated N times is expressed using the predicate rep.

Based on the time relationships set as above, a network of time parameters consisting of start time variables and end time variables is constructed, and synchronization between events is achieved by propagating the values of the time parameters on the network. . In particular, by time synchronizing the start time variable of the parent event and the start time variable of the child event, conversion of the relative time of the schedule of the child event to the absolute time is realized. However, the setting of the time relationship by the predicate occur and the predicate rep with absolute time is realized without using a network. In the case of setting with the predicate 0ccur at an absolute time, the value in the start time variable of the event to be set (in this example, t
l) is only given. Furthermore, in the case of setting using the predicate rep, the number of repetitions is simply given to the repetition number counter of the event to be set.

If the event repetition counter is greater than 0, processing for repetition is performed according to the procedure described in FIG.

Next, a method of synchronizing events using a time-related network will be explained. A time-related network has a form in which time parameters are connected by directed edges, and a certain calculation formula is attached to the directed edges. The time parameter on the starting point side of the directed branch will be called the active variable, and the time parameter on the end point side of the directed branch will be called the dependent variable. FIG. 8(b) is an explanatory diagram showing an example of a method for configuring a network of time relationships of events. In FIG. 8(b), a method of configuring network 7) corresponding to the setting method of FIG. 8(a) is shown (excluding the predicate occur and the predicate rep at absolute time). The network is configured as three sets of tables: active variable names, dependent variable names, and relational expressions. When a value is stored in the active variable, the calculation result of the relational expression is stored in the corresponding dependent variable. Further, if the dependent variable is also registered as an active variable, similar processing is performed using the dependent variable as the active variable. That is, the result of a value stored in a certain variable is propagated one after another on the network. Therefore, when a certain event starts or ends, the values of the time parameter of the event and the time parameters of other events connected on the network are determined one after another, and the times are synchronized.

FIG. 9 is a flowchart illustrating an example of a procedure for propagating values on a network of time-related events. Now, suppose that values are propagated on the network starting from a time parameter tp (which may be a start time variable or an end time variable). First, in step 41, a propagation path on the network starting from tp is determined. To find the propagation path, based on the table in FIG.
, El), (t2. E2), -(tn, En)
) and use this as the search route list. However, tl
.

t2. ...tn is a time parameter, El, E2-E
n is a relational expression corresponding to each time parameter. Then t
l, t2. . . . For each tn as an active variable, all corresponding pairs of dependent variables and calculation formulas are obtained in the same way as above, and merged into the search route list that has already been obtained.

However, time parameters already on the search route list are excluded. By repeating the above operations one after another, the propagation path is found (this is basically a horizontal search).

For example, the search algorithm is
Artificial Intelligence (Sonic Shoten, 1982), Chapter 3. ). Based on the propagation list obtained in step 41, the values of the time parameters are propagated in step 42. Value propagation can be accomplished by sequentially extracting pairs of time parameters and relational expressions from the propagation list, and storing the calculation results of the relational expressions in the time parameters.

(Effects) As described above, the event scheduling method of the present invention realizes repetition of events. Therefore, workers can easily and concisely set event repetitions without having to prepare event settings and time-related settings for the number of repetitions as in the past, improving work efficiency and utilization of resources such as storage space. Efficiency is significantly improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an implementation method of the present invention, FIG. 2 is a conceptual diagram showing an example of the time relationship of events, FIG. 3 is a conceptual diagram showing an example of the time relationship of repeated events, and FIG. 4 is an explanatory diagram showing the contents of an event, FIG. 5 is a flowchart showing the entire event scheduling method, FIG. 6 is a flowchart showing an example of a method for checking the start of a certain event at time T, and FIG. A flowchart showing an example of a method for checking the end of a certain event at time T, FIG. 8(a) is an explanatory diagram showing an example of a method for setting the time relationship of events, and FIG. 8(b) shows the time relationship of events. FIG. 9 is an explanatory diagram showing an example of a method for configuring a network. FIG. 9 is a flowchart showing an example of a procedure for propagating the value of a time parameter on an event time-related network. In the figure, 1 is an event storage means, 2 is an event execution determination means, 3 is a time synchronization means, 4 is an event repetition control means, 5 is an event execution means, 6 is a clock generation means; Figure 3 ↑1↑++ h2t+3t2t2↑11↑12↑13↑
3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 (a) (b) Figure 9

Claims (1)

[Claims] In the event scheduling method, for a repeating event among the above-mentioned events, each time the above-mentioned repeating event repeats, the start time and end time of the above-mentioned repeating event, and the start time of a child event that is a component of the above-mentioned repeating event. , an event scheduling method characterized by resetting the end time.