I am modeling a delivery system and the delivery schedule time is more than one day 24hr. A part of the scheduled time is arranged in the prior day which is shown as a negative number. For instance, -300 means the delivery task to be arranged at 19:00pm on Day-0. 300 means another delivery arranged at 5:00 am on Day-1.
In ideal way, I hope the simulation to be carried out in this form:
#ScheduledMethod(start = -300, interval = 1, priority = 4)
So that I don't have to do any number conversion which will bring a great mess in relation to a lot of schedules.
I tested but it appears that the schedule method needs to start from at least "tick 0". Any solution to this?
Related
I'm trying to find an efficient way to calculate the booked times for a user(object), given a list of free/available times for the same user\object.
I have an object that will return the "available" times for a given specific day. The duration/end time is fixed to 10 minutes.
Example Starting data:
12/23/2020 8:00 AM
12/23/2020 9:00 AM
12/23/2020 1:00 PM
In this case I need to generate the "unavailable" times and insert them into a database with a fairly simple schema:
start_date | end_date | start_time | end_time
The inserting is fairly trivial, i'm having a hard time determining the best way to calculate the unavailable timespans.
Using the example above i would need to generate the following timespans:
12/23/2020 12:00 AM - 7:59 AM
12/23/2020 08:11 AM - 8:59 AM
12/23/2020 09:11 AM - 12:59 PM
12/23/2020 1:11 PM - 11:59 PM
Any frameworks or libraries that can do the heavy lifting on this for me? Is it possible to solve this problem without looping through the results and calculating all of the offsets?
To anyone asking "why" - hooking together two legacy systems, one system returns the available appointments for a given date this needs to be plumbed into a system that needs the un-available appointments for a given date.
Well, first I written more tour booking systems then I can shake a stick at.
The one Rosetta stone that holds true?
You don't want to generate or have booking slots that are NOT being used in the system PERIOD!!!
Thus you ONLY ever enter into the system a valid booking (starttime, and end time). And that startTime should be a datetime column - this will VAST reduce the complexity of your queries. Given you have date and separate time? Well, then your queries will be more complex - I'll leave that to you.
Given the above? The simple logic to find a booking collision in ALL cases is this:
A collision occurs when:
RequestStartDate <= EndDate
and
RequestEndDate >= StartDate
Now in above, I assume date values, or datetime values.
So if I want a list of any booking for today?
RequestDDTStart = 2020-12-23 9 AM
RequestDTEnd = 2020-12-23 5 PM
And thus any collision can be found with this:
strWhere= dtRequestStartDate <= BookingEndDate" & _
" and dtRequestEndDate >= BookingStartDate"
Now, assumging .net, then above would be something like this as parameters
strWhere= #dtRequestStart <= BookingEndDate" & _
" and #dtRequestEnd >= BookingStartDate"
So, above would return all bookings for today 9 am to 5 pm
A REMARKABLE simple query! Now of course the above query could/would include the exam room, or hotel room or whatever as an additional criteria. But in ALL cases the above simple query returns ANY collision for that 9 am to 5 pm.
And the beauty of this system? As long as you never allow a over-lap into the booking system, then you can book a 10 minute or a 20 minute or a 30 minute session as ONE entry into the database. I would thus not need to create 3x 10 minute slots.
So, this means you NEVER have to create booking slots. The whole system will and can be driver with a simple start + end booking record. And as noted, then you can book 1 hour, or 40 minutes. Your input (UI) can simple limit the time span to increments of 10 minutes - but that's the UI part.
Now I suppose to display things in 10 minute increments on a screen? Well, then you would have to submit 6 requests per hour to "display" the time slots. For a whole day, that suggest for 9 am to 5 pm, you would have to run 8 x 6 = 48 requests to get a list of 10 minute increments. But then again, you COULD just show the existing bookings for a day, and allow new bookings to be added - but don't allow if there is a over lap.
So, as noted, the concept here is you don't really need "slots" in the database. I suppose you could try slots, but it makes the code a HUGE mess to deal with. if you ONLY ever store the start + end? Then I can say move the booking to another day by JUST changing the date. Or I can extend a booking from 10 minutes to say 20 or 40 minutes - and ONLY have to change the end time. As long as no overlap occurs with the above simple "test", then I can simple change the booking to be 40 minutes in length - and ZERO code to update multiple slots is required. And same goes for reducing a booking from 40 minutes to 10 minutes. Again ONLY the end time need be reduced - a ONE row update into the database.
So if at all possible, I would dump the concept of having "slots" in the database. I might consider such a design if a booking was only ever 10 minutes. But if 10 or 20 or 30 is allowed, then you don't need to store ANY un-used slots in the database, but ONLY ever store a valid booked slot. Empty un-used time can thus ALSO be found with the above query. (if the query returns records - then you can't book).
So display of free time in some UI becomes more of a challenge, but showing bookings that span 10 or 20 or whatever minutes is far more easy, and as noted, you can even change a whole booking to a different room by a ONE row update of the room ID. If no collision occurs, then you allow this booking - and you achieve this result by ONLY updating one simple booking record that represents that start + end time.
and this means you also NEVER store the booking totals in the database - you query them!
I also found that if I say store any booking totals in the database? Well, with complex code, we always found that the totals often don't match perfect. So then we wind up writing a routine to go though the data, sum up the totals and write those out.
But, if you never store any booked totals (say people on a bus, or people in a given hotel), then while the query for such display is somewhat more difficult, it becomes dead simple to remove a person from say a tour by simple null out of the tourID.
So, this display shows the above concepts in Action. And the available rooms in the hotel, people booked on bus, and even totals for "group tours" are ALL values NOT stored in the database:
So in above, people booked on bus, booked in rooms, and rooms used? All those values are NOT stored in the database. And no slots exist either. So if we have a bus, then we set the capacity of 46, but we do NOT create 46 slots to book into. So be it a bus, a hotel, a medical exam room? You don't create booking slots ahead of time, but simply insert bookings with a start + end, and then query against that concept.
So, to find a total on a bus (or say in a exam room), I query to find the total for that day. And if I want to move a group booking of 4 people from one bus to another? Then one FK update to the given bus they are on allows the whole system to "cascade" the existing values in the system. And same goes for moving a person from exam room #1 to #5. You only have to update the FK value of the exam room. If no collisions occur, then this again is a one row update. If you have multiple exam rooms, and multiple slots, then what should be a simple one row update in the database becomes a whole hodge podge of now having to update multiple booking slots with whacks of code.
So you book "use" of resources "into" a "day" a "bus" a room, but it is the act of that booking that consumes the time slots - not that you pre-create records or timeslots for each "range". This thus allows you to leverage the relatonal database model, and reduce huge amounts of code - since you not coding against "slots", but only that a exam room is open from 10 am to 4 pm. That available room for that day is thus ONLY ONE record you create in the system, and then you are now free to book into that one day given room range. The bookings into that one room for the day can be 10 minutes, or 40 minutes - but it ONLY one record being added into the database to achieve this goal (booking).
Regardless of the above, that simple collision query works for any collision (including a whole overlap, inside a existing span, or even the end or start overlaps any booking. And that query is dead simple - and it works for all collisions. So I don't have a library to share, but that simple booking collision finder query can thus drive the whole system based on that kind of simple query.
I had a question regarding SQL and if you could code it properly to do auto scheduling.
Example
A shipment could come to a store Monday-Friday, but there could only be a certain amount of shipments during this week and it depends which worker was available. I'll run down things in order that way it's not too confusing.
A) A shipment can only stop twice a day, but it cannot stop on a day that has any shipments the day before or the day after. So if Monday had 2 shipments, there would be no stops on Tuesday. If Wednesday has 2 shipments, you could not have any stops Tuesday/Thursday.
B) A shipment can only be so big on these days. If two shipments are both UNDER 1000 pounds, then we can schedule both, but if a shipment is OVER 1000 pounds, then we can only schedule one for that day.
C) One of the two workers must unload each shipment. So lets say that A already has 1 shipment on Monday, I need it to go to B for the 2nd shipment on that Monday.
I understand that SQL cannot accept user input directly, so don't worry about this. Using getdate() would be sufficient enough.
I started on this code and got a little bit in, but the while loop was running for forever (>30 seconds) and I thought it was almost impractical at that point.
Curious if this is doable and the best approach to do this. I'm assuming that C# or something would be loads easier to do with, but wondering about SQL.
Thanks in advance.
I have an access query that will run to calculate the total activity in a location at a specified time. Is there a way to run this over a range of dates and return the results using SQL or should I write a form to run the query various with dates from code?
To make matters slightly more complicated, the query is also dealing with radioactive decay, correcting each item to its current activity at the time requested - although this can probably be ignored for testing.
Finally, on a slightly unrelated note, items and arrive and leave a location at any time, but it is unfeasible to have data points for each second of every day, so I am using three hour intervals as a compromise - as radioactive decay follows an equation, anyone have a better way of doing this (so that data is plotted as soon as an item arrives, otherwise the decay from the arrival time and plotted interval can effect my result a lot) or is this the best I am likely to manage?
Current SQL for single date:
SELECT FORMAT(SUM(Items.Activity*(Exp(-(0.693*(dDate-Items.MeasuredOn)/Nuclides.HalfLife)))), '#,##0.00') AS CurrentActivity
FROM Nuclides INNER JOIN ((Locations INNER JOIN (Items INNER JOIN ItemLocations ON Items.ItemID = ItemLocations.ItemID) ON Locations.LocationID = ItemLocations.LocationID) INNER JOIN LocationLimits ON Locations.LocationID = LocationLimits.LocationID) ON (Nuclides.Nuclide = Items.Nuclide) AND (Nuclides.Nuclide = LocationLimits.Nuclide)
WHERE (((ItemLocations.LocationID)=lLocationID) AND ((ItemLocations.RecieptDate)<dDate) AND ((ItemLocations.DisposalDate)>dDate Or (ItemLocations.DisposalDate) Is Null));
Could no figure out how to solve in the way I initially imagined, so solved as follows instead:
User inputs a date range for the time period they want to view data for.
One query to return single list of all dates when an event happened (date item added, date item removed)
Using set time intervals (now one hour) activity calculated at the time until an event time is reached. At event time activity is calculated for half a second before the event occurred and the time of the event itself. We then continue with our hour intervals until the next event.
After final event keep calculating at the interval until the end time is reached.
This works quickly enough to not be a problem for the user, and the graph is as smooth as it needs to be. FYI activity is also calculated half a second before events to give a vertical slope on the line, otherwise it will be slanted from the previous point (potentially an hour or more of time).
Hi and happy new year to all Optaplanner users,
we have a requirement to plan tours. These tours contain chained and time-windowed activities (deliveries) executed by a weekly changing number of trucks.
The start time of a single tour can vary and is dependent on several conditions (i.e. the goods to be delivered must be produced, before the tour can start; only a limited number of trucks can be served at the plants gates at the same time; truck must be back before starting a new tour). Means: also the order of tours can vary and time gaps between the tours of a truck can occur.
My design plan is, to annotate TourStartTime as a second planning variable in Optaplanners VRPTW-example and to assign TourStartTime to 2-hours time grains (planning horizon is 1 week and tours normally do not start during night times; so the mentioned time grains reflect a simplified calendar for possible tour starts).
The number of available trucks (from external logistic companies) can vary from week to week. Regarding this I wanted to plan with a 'unlimited' number of trucks. But the number of trucks per logistic company, that can be actually assigned with deliveries, should be controlled by a constraint (i.e. 'trucks_to_be_used_in_parallel').
Can anybody tell me, if this is a feasable design approach, or where do I have to avoid traps (ca. 1000 deliveries/week, 40-80 trucks per day) ?
Thank you
Michael
A second planning variable is possible (and might be even the best design depending on your requirements), but it will blow up the search space and maybe even custom course grained moves might become needed to get great results.
Instead, I 'd first investigate if the Truck's TourStartTime can be made a shadow variable. For example, give all trucks a unique priority number. Then make a Truck's TourStartTime a shadow variable: the soonest time a truck can leave. If there are only 3 lanes and 4 trucks want to leave, the 3 trucks with the highest priority number leave first (so get the original TourStartTime, the 4th truck gets a later one).
I've started thinking about an employee shift management application to handle the shifts (who works when, trading, etc) at my current workplace (that uses pen and paper and hasn't got anyway for us employees to communicate about changes without going through the boss and be on site).
Currently the shifts are modeled loosely as:
There is a recurring 4 week period (from Monday week 1 to Sunday week 4)
There is a template for placing employees in this 4 week period
Every 4 months (ie 3 times a year) the 4 week template is projected over the next 4 month period
The shifts have been the same for a long time and it seems many employees would prefer to have them changed (I can say this by the requests for change that come in every time a new 4 month is set).
What I'm aiming at are the models:
Shift_group_tpl (the 4 week period above)
Shift_tpl (a single shift in the 4 week period, including info on who defaults to work this shift)
Shift_group (a set period of time whit actual shifts)
Shift (a set shift whit a real time period and an employee - and the possibility to be changed both in start_time, end_time and employee)
I've thought of a way to do this with recurring iCalendar events: Creating RRULE's (without an endtime) and then calculate (using temporary start and end times) if that specific Shift_group_tpl could be used within a real Shift_group. (The problem with this approach is that I can't figure out how to trim the Shift_group_tpl's to fit into the start or end of a Shift_group.)
What I'm looking for are some other perspectives or ways of doing it or even just a pat on the shoulder letting me know that I'm on the right track (and then giving advice on the trimming problem).
/iole1
What I'm aiming at are the models:
Shift_group_tpl (the 4 week period above)
Shift_tpl (a single shift in the 4 week period, including info on who defaults to work this shift)
Shift_group (a set period of time whit actual shifts)
Shift (a set shift whit a real time period and an employee - and the possibility to be changed both in start_time, end_time and employee)
You have "sql" as a tag for this post? So im guessing you want these as SQL tables?
By the sounds, the problem is that your considering the data you have, rather than the abstract concepts you need to store that data. Which is what you'd need to do to create an application. (Most likely a "Shifts" table, rather than the four tables above).
There is little information here to help, Consider refining your thoughts and ask another question.