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Receiving products from the bottled water manufacturing plant using 11 Rial Guide Vehicles (RGVs) for transportation to the Automated Storage and Retrieval System (ASRS), which serves all three production lines. The RGVs' operation works as follows: when products are placed in the receiving buffer with two available positions, the system immediately sends commands to the RGVs to pick up the products from the buffer. The RGVs prioritize picking up the nearest products first. Consequently, the production line located farthest away (Production Line 1) experiences the highest downtime from January to May 2566, with an average downtime of 449.48 minutes. Production Line 2 has an average downtime of 65.12 minutes, while Production Line 3 experiences 76.00 minutes of downtime during the same period. If a production line stops for more than 20 minutes, it requires a complete drainage of the ongoing production process, including scrapping all unfinished goods. This significantly increases the production costs. Consequently, conducting experiments to address this issue becomes complicated, as full-scale production is necessary to identify the causes and implement effective solutions. Thus, stopping production for testing purposes is not a viable approach in this case.
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This article explores an example model. In this model, items on downstream lanes are able to reserve dogs so that items on upstream lanes cannot use them: reservedogdemo.fsm About Dogs in FlexSim FlexSim simulates dogs on a power-and-free system in an extremely abstract and minimal way. A dog isn't a persistent entity at all. Instead, FlexSim calculates where dogs would be, given the speed, and when they would interact with items. This has a huge performance benefit. But if your logic needs items to interact with specific dogs, this can pose a problem: how do you interact with such an abstract entity? The Catch Condition The only time you can "see" a dog in FlexSim is during the Conveyor's Catch Condition: https://docs.flexsim.com/en/23.1/Reference/PropertiesPanels/ConveyorPanels/ConveyorBehavior/ConveyorBehavior.html#powerAndFree The catch condition fires when a dog passes by an item. If the catch condition returns a 1, the item catches the dog and transfers to the power and free conveyor. If the catch condition returns a 0, the item does not catch the dog. During the catch condition (and only during a catch condition), you can learn many things about a dog: ID - each dog has an ID. The ID is derived from the length of the conveyor and by the distance the conveyor has travelled. If a conveyor is 26 dogs long, the dogs will have IDs 1 through 26. Location - Since an item is trying to catch the given dog, you can derive the dog's location from the items location. Speed - The conveyor that owns the dog is "current" in the catch condition. So you can get the speed of the conveyor at that point. We'll use all these pieces of information in a moment. Creating Tokens to Represent Dogs The first real insight into this model is to make a dummy item. The purpose of this dummy item is to cause the Catch Condition to fire. It never gets on the conveyor. But when the catch condition fires, it makes a token that represents the dog. In this example, that item has a label called "DogFinder" Here is the relevant code from the catch condition: if (item.DogFinder?) { Object pe = current.DogPE; if (pe.stats.state(1).value == PE_STATE_BLOCKED) { return 0; } double dist = current.MaxDogDist; double speed = current.targetSpeed; double duration = dist / speed; if (!item.labels["DistAlong"]) { item.DistAlong = Vec3(item.getLocation(1, 0, 0).x, 0, 0).project(item.up, current).x; } Token token = Token.create(0, current.DogHandler); token.DistAlong = item.DistAlong; token.Conveyor = current.as(treenode); token.Duration = duration; token.DogNum = dogNum; token.Speed = speed; token.DetectTime = Model.time; token.release(1); return 0; } There's a lot going on in this code: This logic only fires for the fake dog finder item If the photo eye just upstream from the dog is blocked, that means there is an item, and this dog is not available. Return here if that's the case. Figure out how long this dog will last (the duration), assuming the conveyor runs at the same speed. In this model, there's a label on the conveyor called MaxDogDist. This is the distance from the PE to the end of the conveyor, minus 2 meters. If this is the first dog ever, calculate the position of the dog, given the position of the item. Store that on a label. Create a token with all kinds of labels. We'll need all this information to estimate where the dog is later, and to estimate how far it is from other items. Pushing Dog Tokens to a List Once the token is made, we need to push it to a list, so that items can pull them. If all your items are the same size, you can just push the token to a list directly. In this model, however, there are larger items that require two dogs. So there's a batch activity first. The dummy item is far enough back that it can detect two dogs and still push the first dog to the list in time for the first lane. So it holds the dog back in a Batch activity until one of two things happen: Either the next dog token appears, completing the batch. Or the max wait timer on the batch expires, indicating that the next dog is not available. Otherwise, there would have been a token. This duration is based on the conveyor's speed and dog interval. If the batch is complete, the first dog in the batch can be marked as a "double", meaning the dog behind it is also available. Once the flow has determined whether the dog is a single or double, it then pushes it to the list. Creating the DistToDog Field When pulling the dog from the list, an item needs to know the position of the dog relative to the item. Is it 0.3 meters upstream? Or is it 2 meters downstream? When we query the set of dogs, we need to filter out downstream dogs and order by upstream dogs, to reserve the closest one: WHERE DistToDog >= 0 ORDER BY DistToDog Here, DistToDog is positive if the dog is upstream, and negative if the dog is downstream. The code for this field is as follows: /**Custom Code*/ Variant value = param(1); Variant puller = param(2); treenode entry = param(3); double pushTime = param(4); double distAlong = Vec3(puller.getLocation(1, 0, 0).x, 0, 0).project(puller.up, value.Conveyor).x; double dt = Model.time - value.DetectTime; double dx = value.Speed * dt; double dogDistAlong = value.DistAlong + dx; return distAlong - dogDistAlong; This code assumes that the item waiting to merge is the puller. So we calculate the item's "dist along" the main conveyor. Then we estimate the location of the dog since the DogFinder item created the token. Then we can find the difference between the item's position and the dog's position. Pulling Dogs from the List Each incoming lane has a Decision Point. The main process flow creates a token when an item arrives there. At a high level, this token just needs to do something simple: pull an available downstream token. If all the items are the same size, it's that simple. But this example is more complicated! If the item is large, we also need to pull the upstream dog behind the dog we got, so that no other item can get that dog. And it gets even more complicated! It can happen that an item acquires the dog after a double dog. In that case, we need to mark the downstream dog as "not double", so that big items won't try to get it. So most of the logic in the ConveyorLogic flow is handling that case. Using the Dog Finally, the item must be assigned to that dog. The ConveyorLogic flow sets the DogNum label on the item. Then, the catch condition checks to see if the dog matches the item's DogNum. Upstream Items The final piece of this model is allowing upstream items to catch a dog on this conveyor. This model adds a special label to those items called "ForceCatch". The catch condition always returns true for those items.
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If you've ever tried to nest groups of objects inside a hierarchy of planes, you may find the drawing of the planes suboptimal and lacking information: Using the container (modified plane) in the attached user library you can represent the container with just an outline. A settings dashboard is installed with the library along with some user commands and global variables. Corner prisms show the nesting layers under the prism: The option 'Use the container center' allows you to use it as either a plane as before or, when unselected, a bordered frame where dropping an object or clicking and dragging within the borders will behave as though you are dropping onto or clicking/dragging the model floor. You can also choose to hide the containers entirely for the cleanest visuals. I hope this will encourage users to use containers more, since when coupled with Templates and Object Process Flows they can increase the scaleability and make your developed assets more manageable. ( In those cases the container becomes the member instance of the process flow or template master and references to its components are made through pointer labels on the container rather than names which you may want to alter for reporting purposes. The pointer labels are updated automatically when creating a new instance of the container.) ContainerMarkers_v1.fsl If you want planes you already have in your model to adopt this style just add this to their draw code: return containerdraw(view,current);
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MQTT is a communication protocol designed for IoT devices. Clients (the devices) connect to a Broker which allows them to publish (send) and subscribe (receive) messages. Each message is associated with a Topic. Each client can choose which topics to use for publishing and subscribing. Usually, the MQTT broker discards messages once they are sent to all subscribers. However, a publisher can mark a message as "retained." This means the broker will keep the last message for that topic and make it available to other subscribers. Only the most recent message is retained. When developing a digital twin, you may need to access these retained messages. This article describes how to do that using FlexSim's Python connection. This article is not meant as a comprehensive guide, but as a starting point, which you certainly will modify for your circumstances. Here are the python scripts and FlexSim model used in this example: MQTT.zip A quick note: since MQTT is a device communication protocol, support for MQTT in the Emulation module is in progress. This article describes how to import data from an MQTT broker like any other file/database/http server, rather than connecting for Emulation purposes. Step 1: Gaining Access to an MQTT Broker Your facility may already have an MQTT Broker running. In the end, your digital twin will need to connect to that broker to retrieve the latest retained messages. However, for testing, or if you don't have an MQTT Broker yet, you can easily get one. One possibility is to use Docker to run the EMQX Broker. However, there are dozens of brokers and installation steps You can download Docker Desktop here: https://www.docker.com/products/docker-desktop/ Once docker is running, you can use the following command in a terminal to download and run the EMQX Broker: docker run -d --name emqx -p 1883:1883 -p 8083:8083 -p 8084:8084 -p 8883:8883 -p 18083:18083 emqx/emqx Note that this command runs a Linux container, so if Docker is in Windows mode, you'll need to switch before running this command. Step 2: Publishing Messages to an MQTT Broker A real facility will have many publishers and subscribers. However, for testing, it can be convenient to create publishers and subscribers that you control. Once your broker is running, you can use code like the following to create a publishing client: https://github.com/emqx/MQTT-Client-Examples/blob/master/mqtt-client-Python3/pub_sub_tcp.py For this example, I created two clients that publish tabular data: one that publishes a set of "raw materials" available for use in the process, and another that publishes a set of "finished goods" available to fulfill orders. To create some data, run the finished_goods_client.py and raw_materials_client.py files for a few seconds each. Note that both of these clients mark the messages to be retained, so FlexSim can access the latest message, even if neither client is actively running. Step 3: Writing a Python Script to Retrieve Messages This approach is demonstrated in fs_client.py, shown here: import paho.mqtt.subscribe as subscribe import json def get_retained_msgs(topics): auth = { 'username': 'emqx', 'password': 'public', } msgs = subscribe.simple( topics, qos=0, msg_count=len(topics), retained=True, hostname="localhost", port=1883, client_id=None, auth=auth, keepalive=5) if type(msgs) == list: return [json.loads(m.payload) for m in msgs] else: return [json.loads(msgs.payload)] if __name__ == "__main__": topics = ["python-mqtt/raw-materials", "python-mqtt/finished-goods"] print(get_retained_msgs(topics)) Run this script to verify that it returns the latest data from the two publishers. When FlexSim calls this function, FlexSim can convert python Lists and Dictionaries into FlexSim Arrays and Maps. So you can return complex data structures directly to FlexSim. Step 4: Writing a User Command to Call the Python Command In FlexSim, create a new user command, and edit the code. Be sure to toggle the node for external use, and set it to the following: /**external python: */ /**/"fs_client"/**/ /** \nfunction name:*/ /**/"get_retained_msgs"/**/ To use Python like this, you need python installed on the path. You also need the paho-mqtt package installed globally. Finally, you need to verify that your global preferences indicate the correct version of Python. For more information on connecting to python functions, see FlexSim's documentation: https://docs.flexsim.com/en/23.2/Reference/DeveloperAdvancedUser/ConnectingToExternalCode/ConnectingToExternalCode.html Step 5: Writing a User Command to Write Messages to Global Tables In this example, the messages we are interested in store tabular data, so it makes sense to store the data in Global Tables: Array tables = ; Array topics = ["python-mqtt/raw-materials", "python-mqtt/finished-goods" Array msgs = getRetainedMessages(topics); for (int m = 1; m <= msgs.length; m++) { Table fsTable = tables[m // header code elided; see example Array msgData = msgs .data; Table msgTable = Table(msgData); msgTable.cloneTo(fsTable); // header code elided; see example } If you run this new user command, you can see the latest data pulled in to FlexSim. Conclusion This example shows just one way you could import data from an MQTT broker into FlexSim. In addition, the kind of data you import or what you do with that data is up to you as the user.
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In the attached model we use a Timetable and two MTBF/MTTR objects to define Schedule Loss, Availability Loss (breakdowns) and an element of Performance loss due to short stops (state Down). The processor sends 'bad' items to port 2 based on the send to percentage which account for QualityLosses. The processor's 'best' processing time per part (5 seconds) is stored as a label, while the processing time itself is a triangular distribution with the minumum as 5 seconds - so it also contributes to performance loss. When the Type of the item changes a setup time occurs which is the final contributor to performance loss. Two state profiles were added to the processor - one to track production time and another for availability. An object process flow on the processor detects production profile state changes (between On and off shift) and regular Flexsim state changes and determines the availability state that should prevail. A user command getOEEstat is used to access the values which it calculates on demand and stores in a label on the processor called statsMap. The syntax for this command is: getOEEstat(myMachine,"OEE") The list of stats: "ScheduleLoss","AvailabilityLoss","PerformanceLoss","QualityLoss","IdealProdTime","AvailabilityRatio", "QualityRatio","PerformanceRatio", "IdealProdTime", "RunTime", "OEE", "TEE". A group was used to indicate which objects have their OEE tracked, and a stats Collector reads the group members and adds rows at reset. Finally Performance Measures were added for the stats for processor 1. Processor_OEE_2.fsm 2023-08-22 Update: Added 'TEE' stat.
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FlexSim 2019 Update 2 is available. If you have bug reports or other feedback on the software, please email [email protected] or create a new idea in the Development space. Release Notes Added a Storage System object to improve warehouse modeling. Improved the Rack object. Added more types of racks to the library. Updated the Sketchup SDK to load newer skp file versions. Added a ray tracing render mode. Added a Color Palette tool. Improved the color picker popup. Updated dashboard charts to use color palettes. Added options for showing column names to charts. Added options for showing multiple Y-axes on timeplots and histograms. Updated box plot options for categorizing and coloring data points. Added an option for reordering axis categories on timeplots, histograms, and box plots. Added additional line styles and visualization options to timeplots. Added Table methods for using indexed columns. Added a resetvalues attribute. Added Object getVariable() and setVariable() methods. Updated the SQL IS keyword to work with expressions. Improved performance of SQL queries on tables with indexed columns. Added an array parameter to Math.max() and Math.min(). Added a binary bundle field type. Added a button to Model Settings to export embedded media. Changed the default Person flowitem into separate Man and Woman flowitems. Added options for using the object's color to Person Visuals. Added a changepersonvisuals() command and pick options. Updated the Model Background properties window. Added a right-click option to show/hide model backgrounds from the Toolbox. Added pick options for using lists to the Pick Operator field on the processor. Updated various pick options to use generic label references. Added options to the List for special handling of SELECT values. Added Text options to Quick Properties. Added mean and standard deviation to the statistical distribution popup. Added icons to various pick option menus. Improved the Copy Variable function of Edit Selected Objects. Added the location coordinate system button to the General tab of object properties. Removed the Build menu; its options can still be added to the user toolbar. Changed the run speed slider to behave as a ratio of real time instead of model units per second. Changed the color of the selection box in the 3D view to be more visible. Fixed a bug with deleting array data from a node. Fixed an exception with cloning a table without rows. Fixed a bug with applying experimenter triggers. Backwards Compatibility Note: the following changes may slightly change the way updated models behave. Improved the rendering performance of some imported shapes by optimizing their meshes by material. Some mesh customizations may apply differently for some shapes. Charts now ignore null values instead of trying to categorize or plot them. Changed the FlexScript + operator to concatenate numbers with strings. Fixed some FlexScript math operations with numbers and null variants. Fixed an issue with FlexScript downcasting not always type checking properly in certain expressions. For example, "Object obj = param(1);" will now correctly throw an exception if param(1) is a treenode without Object data. Updated the Rack's place offset to be the actual location that the item will be placed. Fixed a bug with labels added during events at time 0 not being deleted on reset. Fixed a bug in Color.random(). Process Flow Changed the scroll wheel to zoom instead of panning the view up and down. Removed the extra outline around stacked blocks. Changed the default option for Release Batch on max wait timer and max idle timer to have Failed unchecked. Organized the ProcessFlow list on the toolbar based on the Toolbox folder structure. Changed Event-Triggered Source and Wait for Event panels to be collapsible. Added an edit field for the number of arrivals on the Scheduled Source. Added a getlastacquiredresource() command. Changed the color of the selection box to match the 3D view's. Backwards Compatibility Note: the following changes may slightly change the way updated models behave. Updated Move Object's Preserve Global Position checkbox to preserve location and rotation. People Added an experiment variable for changing the number of objects in a People group. Added a visual indicator to show when objects are acquired by the shift schedule. Added A* dividers to waiting lines and other objects. Added a custom window for People Down Behaviors. Added a Keep Person on Transport checkbox to the Transport Person activity. Changed the default Arrivals activities to randomize the created person's visuals. Added state history tables. Adjusted the Staff's walk back to reset position so that it is preempted if acquired by something else. Updated activity subflows so travelers synchronize their speeds when traveling together. Moved copying token labels to the created person to after the people settings labels are added so values aren't overwritten. Fixed a bug with getting the value of certain types of labels defined in People Settings. Walls are now created at the current Grid Z height. Conveyor Improved naming of various objects. Fixed a bug with the height of decision points when created with certain model units. Added a chain texture to conveyor belt visual options. AGV Updated curved path quick properties to be able to specify start and end points. Improved naming of control points and areas. A* Added the A* Navigator to the Toolbox. Updated the A* Navigator Properties window.
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The FloWorks module has been updated for FlexSim 2017 and is now available (December 2016). Update 1: Bug fix update 1 was released on Jan 23, 2017. Update 2: Bug fix update 2 and FloWorks 17.1 for FlexSim 2017 Update 1 were released on Apr 11, 2017. FloWorks is a 3rd party module developed and maintained by Talumis BV ( talumis.com). It provides faster and more accurate modelling and calculation of fluid systems than the default FlexSim fluid library. It is especially useful within the oil, gas, and bulk industry both for production and supply chain optimization. This module requires a FloWorks license. For any questions, please email [email protected]. Release notes FloWorks version 2017.0.1 (Jan 23, 2017) Bug fix: Missing names and items in Flow Item Bin fixed. Bug fix: Properties window for Flow Tank flow item now opens correctly. Bug fix: Resolved some minor issues with "Add to dashboard" pins. FloWorks version 2017.0.0 (Dec 22, 2016) FloWorks updated for FlexSim 2017 Flow Mixer now has a manual mode, that will put it in Idle mode after each batch until you manually call StartMixerRecipe. Allow Input Rate and Output Rate to be plotted versus time. New Workability and Level Triggered Event objects added with focus in particular on modelling of ports and offshore processes. Unfilled part of Flow Tank is no longer necessarily gray but takes the object color. When Impact Events are active on a FloWorks object, they will show a box around the object similar to the "stopobject" behavior in standard FlexSim. The color of the box varies from red (0) through yellow to green (1) to black (infinity) depending on the impact factor of the event. Dropdown lists for port actions improved. For example, you can now open or close a single port (OpenFlowIp c.s.), select an individual port to open, close input and open output, etc. Increased limits on number of objects and events when running unlicensed version in FlexSim Educational version. Bug fix: Can now add Object Groups to FloWorks charts. Bug fix: When changing a Flow Task Executer from vessel to truck, the TE's flow tank is correctly scaled and positioned on reset. Bug fix: The State display in the Quick Properties did not correctly show the state of the Loading Arm. Bug fix: Arrow heads can now be dragged by holding 'X' key instead of Alt. User commands consolidated and documentation updated: ConnectFlowObjectToOtherObject command rewritten and documented. All documentation in modules\FloWorks\help\Commands reformatted and automatically generated based on actual user commands. These help pages often provide more explanation on the parameters and their optional values, the return types, and more extensive examples than the FlexSim Command Helper pages. Integration with the Process Flow module: FloWorks options added to "Listener Initialized" trigger of "Wait for event" action. Dropdown lists for port actions improved. For example, you can now open or close a single port (OpenFlowIp c.s.), select an individual port to open, close input and open output, etc. Backwards Compatibility Note: the following change may slightly change the way updated models behave. The Item To Flow's OnItemEmptied trigger is now fired before the actual item is destroyed, so that you are still able to reference it in the trigger code.
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I created this custom visual tool because I had a situation where we needed to see the progress of activites in the 3D View. I basically just change the size of a plane based on the completion level and calculate a percentage. Model is attached and contains some explanations. Enjoy, Custom visual tool.fsm
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Every now and then, there are technical support questions that are asked more than once by different users. This article seeks to address a couple of “how to” questions that have come up over time. As such, this isn’t a massively technical paper just a quick look at a few things that might make your modeling experience more fun and your models a little more interesting. Background: This is a physical screening clinic similar in nature to those you might encounter either in the military or in a hospital that supports a large industrial area where employee physicals are required either by insurance companies or an employer. That said, it could even be a part of a much larger function like an ER. In a nutshell, patients that represent a mixed population of both men and women, are sent to the clinic without an appointment and arrive according to an exponential distribution. In the model, the mix of men and women is 50-50 although it can be altered to accommodate any distribution of patients. Once a patient registers, he/she is either directed to a gender-specific changing room where they change into a white surgical gown, or take a seat in the waiting room until a changing room is available. Once changed, each patient is escorted to an exam room by one of two nurse practitioners, is examined for a time period that is also gender-specific (men – normal(20,5,1), women – normal(17,3,1)), and is eventually released to return to a changing room and finally to leave the clinic. Any time there is no changing room available, patients take a seat in the waiting room. The clinic opens at 0800 hrs and closes at either 1600 hrs or after 1600 hrs when the last patient departs. Open and run the model, “changing-rooms-model-11-16-2016.fsm” to see the model in operation. Modeling challenges: The challenges are straight-forward and not at all complex. Specifically, they address the following questions: How do you stop patient arrivals (e.g. in-flow) at a certain time of day and then close the clinic when the last patient departs? How do you make sure that patients go to their own gender-specific changing rooms? How do you change a patient’s shirt color to white representing a patient gown and then back to their original color when they change back into their street clothes? How do you use a patient label to determine treatment time if a distribution is contained in the label? Flow Chart: Before we dissect the model, it’s probably not a bad idea to take a close look at the flowchart if only because, despite the model’s size, it can seem a little complex. Notice that the changing rooms really are the central point in the model. As such, connecting lines have to be constructed that link the Registration Area (0ne way), the waiting room (two way), the exam area (two way) and the Patient exit (one way) with each of the Changing rooms. Setting the Stage: Because the purpose of this model is to make provisions for and track both male and female activities, it uses two different PCIs (Patient classification Index numbers) to represent Men (PCI1) and Women (PCI2). Those PCIs and any related labels that may generally carry information about patients that might be used for decision making later, are initially entered in the Track Manager, under the tab labeled, "Patient Classification” as shown to the right. Note that, in this case, there are fields for identifying which Track a specific PCI will follow, what each PCI’s Acuity will be, which Gender different PCI’s will represent, which distributions represent each PCI’s Exam Time in the model, and a direct reference to which changing room a patient should use. Needless to say, each of the three types of fields – text, number and code – are accessible from various elements of the model and may be used to determine and isolate almost any patient characteristic a modeler might use to define patient Activities. One other “setting the stage” aspect of the model that deserves mention is the positioning of the nurses. Note that the two nurses aren’t arrayed in a single line, the default positioning of resources in a model, but rather are positioned as if they're having a conversation. Although somewhat inconsequential when a resource staff is small, large collections of staff members cry out for better, more life-like poses. To change a resource’s initial location in a model relative to its home base - in other words, it’s “Offset” – first make sure the model is in “3D View” by clicking on View>Model View (3D) in the main menu. Then, simply click on the individual resource and drag it to the place you’d like it to stand as its initial position. Note that the X Offset, Y Offset and Rot Offset values that are unique to each member of a resource group, will automatically be changed to the new coordinates. Finally, note that by clicking and holding down your left mouse button over any of the Offset positioning arrows (circled in red above), and then moving your mouse forward and back, you can also manually reposition any specific resource. Arrival Pattern : Open the Properties window for the Patient Arrivals Object to follow this discussion . The Patient Arrival pattern is simple to construct, involving nothing more than identifying the correct exponential distribution (i.e. exponential(0,20,1)) in the Patient Arrivals Properties’ Interarrival Time field as shown at the left. Notice also that the Patient Classification Index (PCI) field contains an expression to calculate and therefore generate two different PCIs. As mentioned previously, PCI 1’s are classified as men and PCI 2’s as women. In this case P(50.00, 1, 50.00, 2) insures that a mix of 50% men and 50% women will be generated by the Patient Arrivals Object during the model run. Setting Certain Patient and Model Characteristics : The purpose of the Patient Arrivals object isn’t only to create a unique pattern of patient arrivals but also to serve as the source of every patient’s initial characteristics as well as set certain actions that affect the performance of the model as a whole. In this case, changes to the patient’s appearance and the stopping time for patient arrivals are both determined in two different Patient Arrivals’ Property Triggers as shown at the right. Note that the “On Creation” Trigger is used to identify any actions the modeler might want to activate that occur when a patient is created for entry into the model. As shown, picklist option can be used in the On Creation Trigger to change any number of model parameters In this model, only that referring to the patient’s shirt color is changed. In this case, there are three entries to select from … (1) the fact that the patient’s shirt color should be changed, (2) which color palette should be used to obtain the desired color (Palette2), and (3) which color (by index number) should be used. Note that the color index number is determined by the patient’s PCI of either 1 or 2. Different palettes unique to the software can be viewed by selecting, “Edit > Color Palettes,” from the software’s main menu. Note that new palettes and/or colors may be added to the color palette editor by selecting the appropriate functional options (ie. Add/Delete Palette, More/Less colors). In this case, Male patients will wear green shirts and female patients will wear yellow. Note that the “OnExit” Trigger is used to identify any actions the modeler might want to occur when a patient exits the Patient Arrival object. In this case, the picklist option, “Stop or Resume Flow” is selected to act as a brake for patient arrivals after a specified elapsed time. Although there are seven different drop down options to select from regarding the condition desired to stop patients from entering the model, the option “time()>960” is selected to stop arrivals at 1600 hrs (4 p.m.). Note that “960” represents the elapsed time in minutes since midnight (time 00:00) of the first day of the model run. Many first time modelers make the mistake of assuming that the time value represents the elapsed time since the model’s beginning time, in this case 8 a.m., which isn’t the case. In any event, this picklist option examines the time of every patient’s departure from the Patient Arrivals object and the first patient created at or after 1600 hrs, automatically stops any additional patients from being created. Closing the Clinic’s Doors and stopping the model . Open the Properties window for the Patient Exit object to follow this discussion. Clearly there are two actions that are required to close the clinic at or after 4 p.m. when the last patient departs. The first is to close the front door which is accomplished by the “OnExit” Trigger found in the Patient Arrivals object as discussed in paragraph 5B above. The second is accomplished in the Patient Exit object’s “OnEntry” Trigger as shown at the right. In this case, the drop down picklist option, “Stop Model Based on Condition,” is selected and used to establish two criteria for the model’s end. The first criteria is that the elapsed time be later than 4 p.m. and the second is that there be no patients in the clinic when 4 p.m. arrives. The correct entry for the picklist option then, is shown at the left and takes both circumstances into account. What it determines every time a patient leaves the clinic is, what time it is and if anyone remains to complete treatment at that time. If the time is even a second past 4 p.m. and the clinic census is zero, the expression stops the model. So far, we’ve accomplished several tasks that include, (1) setting the patient’s shirt color, (2) establishing a criterion for closing the clinic door at 4 p.m. and stopping clinic operations at or after 4 p.m. when the last patient leaves, and (3) positioning resources at various places in the model rather than in a single straight line. Now, we need to change the patient’s shirt color to white – symbolizing changing into an examination gown – and back to its original color when the exam is over, and determine the patient’s Exam Time. It’s a simple process that we’ll cover in Activities 40, 60 and 80. Activity 10_Arrival: This activity causes the patient to walk unescorted from the Patient Arrival Object to the Registration Area. Although there’s nothing complex or unfamiliar about the activity, it’s important to note that even though this activity has no predecessors, a check mark is still required in the Predecessors box to cause the model to begin this activity without a command from some other activity. Activity 20_Registration : This activity causes the patient to use someone from the ClerkGroup at the Registration desk for normal(2,1,1) minutes to log in. Activity 30_TravelToChange1:This activity causes the patient to walk unescorted to one of the two changing rooms based on the patient’s sex. As such, which of the changing rooms is determined by the entry in the Patient Destination field, in this case, from the drop down picklist option, “Based on a Condition,” and by the edited drop down option, “getlabelnum(patient, "Gender") == 1 as shown to the right. Note that there are actually 12 different, “Choose a Condition” options the modeler can employ to set the patient’s destination. Activity 40_Change1 : This activity causes the patient to take normal(3,1,1) minutes to change into an examination gown and changes the patient’s shirt color from either green or yellow to white representing that change. The expression that causes the color change is contained in the Advanced Function, “Activity Finished Trigger.” In this case, the drop down picklist option, “Set Color” is selected to change a patient’s shirt to white as shown to the right. White is the color whose index number is 15 in the color palette 3. Activity 50_TvlToExam: This activity causes the patient to be escorted by a member of the NurseGroup from the changing room to the first available Exam room. Activity 60_Exam : This activity causes the patient to spend a period of time specified in the Processing Time field being examined by the same nurse that escorted them to the Exam room. Note that the exam time is entered by selecting the drop down picklist option, “Based on Patient’s Label,” and then by selecting the Patient Label, “ExamTime,“ that was previously set in the Patient Classification Index (PCI) Table. See Paragraph 3 above. Activity 70_TvlToChange2 : This activity causes the patient to walk unescorted to one of the two specifically named changing rooms. As such, which of the changing rooms is determined by the entry in the Patient Destination field, in this case, from the drop down picklist option, “Based on a Condition,” and by the edited drop down option, “getlabelnum(patient, "Gender") == 1 as shown to the right. See paragraph 7C for the same logic initially entering a changing room. Activity 80_Change2 : This activity causes the patient to take normal(3,1,1) minutes to change out of their examination gown and back into their street clothes by changing the patient’s shirt color from white back to their original color. The expression that causes the color change is contained in the Advanced Function, “Activity Finished Trigger.” In this case, the drop down picklist option, “Set Color” is again selected to change a patient’s shirt to its original color using the patient’s PCI number. Note that this is the same way the shirt color was assigned initially. See paragraph 5A Activity 90_Departure: This activity causes the patient to walk unescorted to the clinic exit and leave the model. Special Notes regarding the Changing Room model . As simple as the model may seem, it serves to reinforce several modeling techniques that we sometimes overlook. For example, … All activities are assigned unique Milestone names. In this case, TvlToChange1 and TvlToChange2 are identical in every respect. However, Change1 and Change 2 aren’t. To combine the four different activities into two identical activities would change the Patient Timeline widget in the Dashboard so that a patient’s time spent waiting for a nurse following the first Change would be combined as a single display element. This might make it difficult to glean specific information from the Timeline regarding total time changing and waiting for resources. The use of floor displays and walls to enhance a model’s appearance is highly encouraged. To design effective and realistic models, practice using the Infrastructure tools to create underlying floors and the Library tool, “Visual Objects,” to create enclosures.
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We recently had a customer ask how to draw a flow item label on the flow item object. I thought that this information would be useful to other FlexSim users as well. In the 3D model, drag and drop a Text visual from the Library. Select the text in the 3D model, then copy it to the clipboard using Ctl + C Go to the Toolbox tab, open the FlowItem Bin, and double click the Flow Item of interest. Right click the 3D flow object, and click "Explore Tree" Click in the white space underneath the Flow Item's node, and use Ctl + V to paste the text as a subnode to the flow item. If you zoom out in the Flow Item's 3D view, you will see the text. You can double click on the text and use the General tab to position it wherever you would like. Double click the 3D Flow Item. Underneath the Labels tab, select the green plus sign to add your label. In my example, I added a number label called "Type" with a default setting of 0. Click "OK". Double click the text that you added in step 5 and 6. Underneath the Display tab, click the custom code button next to Text Display. Within the custom code type something like the following: /**Custom Code*/ Object current = ownerobject(c); treenode textnode = param(1); textnode.value = "Type: " + string.fromNum(current.up.Type); //Note: If your label is called something other than "Type", make sure to replace it in both places. Click out of the "FlowItem Bin" tab and back into the "Model" tab. Double click the source where your Flow Item is being created. Underneath the Triggers tab, add an On Creation trigger. Click the green plus next to the On Creation trigger. Hover over Data and select "Set Label". Make sure the text next to the Label field matches the text of the label you set in step 7 and 8. By following these steps, each Flow Item will have a text label that displays the Flow Item label next to the Flow Item object. Please see the attached gif for a demonstration. flowitem-label.gif
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In this example model you'll see two identical elevator setups. However, you will notice that ElevatorBank1 allows the patient to move to the next floor properly, whereas ElevatorBank1_2 will float the patient up the network node instead of using the elevator. There are a few steps you must follow to ensure you will have a properly working elevator in your model. Make sure everything is working the way you intended, without an elevator. Now you can add in the elevator, select it and then check the 'Connect to Path' box as seen below Now ensure that the elevator is connected to the nearest path node and any nodes above it. One thing to note is that after resetting if you click on any of the Path nodes that the elevator is connected to you will see that the On Arrival Trigger now says Send Message to Request Elevator. This is the code that actually calls the elevator when a patient arrives at the node. The elevator automatically adds this to the nodes connected to when resetting, but this trigger option can be added to any node. Another good practice, especially if patients walk by the elevator without always using it, is to make a separate node off on a spur. That way patients aren't triggering the elevator every time they walk by.
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Here on Answers it's often helpful to post code in a question or an answer. When you do so, there are certain steps that should be taken to avoid being blocked by Answers' internal security mechanisms. This article describes the proper way to submit code without arousing suspicion from our threat detection software. Some of our customers are all too familiar with the screen below after asking a question or adding a comment that includes code. What is Cloudflare? Cloudflare is a 3rd party threat detection software specifically designed to detect malicious code/software that may threaten a website. Once you've seen this screen above, there is no way for us to un-block you, as it is an automated 3rd party software. Unfortunately, at this point you have to wait a variable amount of time until Cloudflare decides your IP address is no longer a threat and you will again be allowed access to answers.flexsim.com. What am I doing wrong? This warning usually presents itself when code has been typed or pasted directly into the body of your post, like this: How do I properly format my code? First paste or type your code into the body of your post. Then, highlight your code and click the Code button in the toolbar. It looks like this: < > How can I tell if my code is properly formatted? After highlighting your code and clicking the code < > button, you will see that your code now has a border and light background: Remember, if you have multiple blocks of code, you can select just the code you want to be grouped together in the first block, hit the code button in the toolbar, and then select the second group of code and again hit the code button to make the second code block, etc. After you submit your post, you will see your code formatted with syntax highlighting, a mono-spaced font, and the lines numbered, like this: Conclusion Adding code to your post is an essential task for many of our customers. If you follow these guidelines, you should be able to avoid being blocked and ensure you have uninterrupted service on our answers site. If you feel you have properly entered code and are still being blocked, please inform us and include the code and method of formatting you were using when you were blocked. We'll gladly look into it. As a fallback, you can take a screenshot of your code and add it to your post as an image, but still let us know there was an issue, and we'll look into it. Finally, if you're in a hurry and Answers troubles are keeping you from getting the help you need, remember to contact your local FlexSim representative directly by phone or email.
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FlexSim 2022 Update 2 is now available for download. For more in-depth discussion of the new features, check out the official software release page: Official Software Release Page - FlexSim 2022 Update 2: AMR Modeling, AI with Bonsai, and more You can view the Release Notes in the online user manual. FlexSim 22.2.0 Release Notes If you have bug reports or other feedback on the software, please email [email protected] or create a new idea in the Development space.
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FlexSim 2021 Update 2 Beta is now available (Updated 26 July 2021) To get the beta, log in to your account at https://account.flexsim.com, then go to the Downloads section, and click on More Versions. It will be at the top of the list. The More Versions button does not appear when logged in as a guest account. Subsequently the beta is available only to licensed accounts and accounts that have a license shared with them. Learn more about downloading the best version of FlexSim for your license here. If you have bug reports or other feedback on the software, please email [email protected] or create a new idea in the Development space. FlexSim 21.2.0 Release Notes Added a Template system for inheriting properties from other objects. Added new manipulation handles for moving, rotating, scaling, and connecting objects in the 3D view. Added ability to delete connector lines. Added a StateTable object. Added a getstatetableutilization() command. Added a Pass-through parameter type. Added a checkbox so transporters can move their forks separate from traveling. Added more Task Executer shapes. Improved treenode.getPath() to return a relative path to nodes that aren't a direct ancestor. Added a Frustrum Culling checkbox in Visuals. Agent Added an AgentSystems property. AGV Allowed the user to define some basic routing cost multipliers, including: An option to divide by speed, allowing for fastest path routing (instead of shortest path) An option to define a custom path-based multiplier to the cost Added Path Conditions, which allow you to "close" certain paths, based on either model state or agv state, etc. Added a Prioritize Control Point Lookahead option. A* Added the capability to have oblong grid node sizes. Allowed barriers to be inside visual tools. Added the ability to add dynamic barriers to the A* system. This is done by calling AStar.navigator.addDynamicBarrier(), then AStar.navigator.removeDynamicBarrier() to remove those barriers. Added several triggers to A* objects: AStar.Navigator: OnGridChange: called when dynamic barriers are added or removed AStar.Traveler: OnCalculatePath: called just before a traveler's path is being calculated AStar.Traveler: OnNavigatePath: Called just before a traveler runs the algorithm to define kinematics and cell allocations for traveling its path. Also allows the ability to override the default behavior and define your own. Made several additions to AStar.Traveler API, AStar.Navigator API, etc. Added a TravelPatterns property. Backwards Compatibility Note: The following changes may slightly change the way updated models behave. Improved the deadlock recovery algorithm. Now it will add each traveler in the deadlock, as well as any travelers that are waiting on those travelers, as dynamic barriers. Then it will go through each traveler in the deadlock, remove it from the dynamic barriers, add any additional travelers that are adjacent to that traveler as barriers, then try to recalculate the path to the traveler's destination. If it finds a traveler that can still travel all the way to its destination, that traveler will be rerouted. Otherwise, if it finds a traveler that can travel at least on grid square, it will reroute that traveler. Otherwise, it will give a notification of unrecoverable deadlock. GIS Added the GIS module to the Flexsim Installer. Process Flow Added a ProcessFlows property. Added a ProcessFlowVariables property. Backwards Compatibility Note: The following changes may slightly change the way updated models behave. Removed instance object editing from Object Process Flows.
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A narrated video demonstration of the FlexSim Healthcare Tutorial described in the FlexSim 2020 User Manual has been released! Here is a link to the written documentation: https://docs.flexsim.com/en/20.0/Tutorials/FlexSimHC/OverviewFlexSimHC/ Here's a link to the video: https://vimeo.com/394012280
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"switch by case" is a stucture in many programming languages. It is a availbale in Flexscript. A case must be a number for a switch by case structure in Flexscript. A decide activity can switch even to string value cases. All you need is to rename the connector from a decision activity to a following activity. process_flow_by_case.fsm
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You should have already completed all preceding steps found in the article Hosting your FlexSim licenses with lmtools, including all those under the headings "Preparation and Prerequisites" and "Activate licenses to your license server". At this point you're ready to install, configure, and start the service that will serve your FlexSim licenses.   Create the service Configure service permissions Start the service Check the service status Troubleshooting problems with the service   Create the service   We'll use lmtools to create your new licensing service.   On your license server, in your extracted download folder of FlexSim license server materials, right-click lmtools.exe and choose Run as administrator. Go to the Config Services tab. Create a new licensing service by typing FlexSim_License into the Service Name input field. The Service Name field looks like a dropdown selector, but you can click in it to type a new name. Use the 3 Browse buttons to specify the paths to files (lmgrd.exe, flexsim.lic, log.log) that are also included with the FlexSim license server materials. Check the boxes for Use Services and Start Server at Power Up. Press the Save Service button in the upper right. Confirm the save by choosing Yes. You may receive an error message regarding "Windows preferred path". This is normal and this message can be safely ignored.   Configure service permissions   Your new FlexSim_License service needs permissions set to function properly.   Click the Windows Start button or press the Windows key, then type “Services” into the search box in the Start menu, and press Enter. Windows will search for and open Windows Services Manager. Find FlexSim_License in the list of services. If it is missing from the list, see the section Troubleshooting the licensing service below. Open the FlexSim_License service’s Properties window by double-clicking its name. Go to the Log On tab. Choose the option to Log on as: Local System account. Press OK to close the FlexSim_License Properties window.   Start the service   While still in Windows Services Manager, use the Start link to start your new FlexSim_License service.     You should see a status bar showing the startup progress. The service usually starts in under a minute.   If there are any errors or other problems with starting the service, skip to the section Troubleshooting problems with the service.   Check the service status   After the service is started, head back to lmtools to check the log. You can view the service log from the Config Services tab, press the View Log... button, located toward the lower right of the Config Services panel.   You should find the following information in your log file:     lmgrd.exe is listening on port 26914. This is the port the licensing service will use when listening for client PC communication. The bootstrap license file flexsim.lic was found and loaded. (This is not a license file specific to you and does not contain your license info. FlexSim licenses use Trusted Storage and licenses are activated to your license server using flexsimserveractutil.exe). The flexsim.opt Options file was found and loaded. A list of product features activated in your server's Trusted Storage. Your feature set may differ somewhat from this example, depending on your license and product, but you should see several of the features above. 900 seconds is the minimum timeout allowed by FlexNet, and we configure our installation to use this minimum value using the options file. The flexsim.exe vendor daemon is using port 56914.   To close the log, press the Close Log button, toward the lower right of the Config Services panel in lmtools.   Troubleshooting problems with the service   Did everything work? If not, perhaps you have one of these issues:   The FlexSim_License service is not listed as an installed service in Windows’ services. The FlexSim_License service does not start manually. The FlexSim_License service does not start up automatically when the computer restarts.   If any of these apply to you, please check the following:   You ran lmtools as a user with admin rights, and right clicked the program to choose Run as Administrator. On the Config Services tab, you checked the boxes Use Services and Start Server at Power Up. There isn’t already a process running or service installed named FlexSim_License. lmgrd.exe, flexsim.exe, and all other files downloaded together with them are in the same folder, and in a file path that does not contain any folder named “FlexSim” (case insensitive). The FlexSim_License service must run as an account with proper permissions. It’s possible that the Local System Account setting specified in Configure service permissions above does not have adequate permissions, and you will need to specify the service to run under a different account. Work with your server administrator or IT department to determine an account with the proper permissions to run your license service. You could have a port conflict, where one or both of the ports specified in your flexsim.lic license file are in use by another service on your license server. Check the section Resolving port conflicts. Some anti-virus solutions prevent unrecognized services from running or accessing necessary functionality. If your license service won't start, try temporarily disabling any anti-virus solution installed on your license server. If this fixes the issue, work with your IT administrator to modify your anti-virus settings. Remember to reactivate your anti-virus software after this experiment.  
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Modeling LWBS patients is tricky business and can cause exception errors under certain circumstances if not done correctly. The problems usually arise due to patients who exit the model early while there are pending requests queued up in the model for future activities on the patient. The attached model demonstrates the current best practice for safely modeling LWBS patients without the possibility of generating unwanted errors. The modeling technique is very simply. Use the On Entry trigger of the waiting room object(s) to send a delayed message to itself in X minutes, where X is a sample time from an "impatience curve" representing the amount of time a typical patient is willing to wait before they strongly consider leaving. In the On Message trigger of the waiting room object(s), I have written a code snippet that you will want to copy and modify to suit your own modeling requirement. The code snippet in the example model checks to make sure the patient is still in the waiting room waiting for an exam room at the end of the "impatience time" when the message trigger fires. Then I roll the dice using a bernoulli distribution to decide whether or not to have the patient actually leave. The code snippet shows a different probability for each of two patient types (PCI's) and then a default probability of 50 percent for anyone else. Not only does this modeling approach avoid undesirable exception errors, but it is also more accurate and definitely more efficient than using the Quick Properties fields in the Patient Condition panel of a waiting room which requires repetitive function calls every so many minutes throughout the model run!
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One of the most powerful commands in FlexSim is the query() command. It allows you to run SQL-like queries on virtually any data structure in the tree. If you don't know what that means, or what SQL is, or why it would be good to have SQL in FlexSim, this article is for you. If you have general ideas, but you would like to know more, then this article is for you. This article is not about connecting FlexSim to an external database. If that is your goal, then this article is not for you. Basics - Tables Data is often arranged in a table, which very loosely means that data is organized into rows and columns. However, SQL (and therefore the query() command) was designed to work only on certain kinds of tables, that look something like this: Name Age Fur Color Scooter 6 Brown Spot 3 Brown Whizby 4 Black Notice the following points about this table: Each column has a unique name There are no row headers (although if your table in FlexSim has data in the row header, that's okay; we'll get to that later) The table is a list of things, and each row in the table represents a single thing. The columns tell you the data that is stored about each thing. In this table, each thing is a pet, and each row stores the name, age, and hair color (the columns) of each pet. If our data included another pet, it would make another row in the table. In database lingo, a row in a table is called a record. One other thing you need to know about this table is that it has a name (in this case, "Pets"). All tables in SQL have a name, and follow the format described previously. Basics - Tables In FlexSim FlexSim has several different ways you can store data. Most users employ Global Tables and Lists (found in the toolbox) to manage data in their model. More advanced users sometimes create tables or bundles on labels. Then there's the model itself, which stores your object's locations in a tree data structure. All the data about where and object is, and how big it is, is stored in the model tree. So which of these data structures meet the standards for a SQL table? As far as the query() command is concerned, all of them do. The query() command is flexible enough to handle any data structure. The trick is to imagine your data as a table. To do this, you need to be able to answer the following questions: How many rows are there? What columns will the table have? How do you get the data for each cell? Phrased another way, given a row and a column, how do you put data in the table cell? If you can answer these questions, you can use the query() command. Let's apply these questions to two data structures in FlexSim: the Global Table, and the Global List. For the Global Table, the answers are very straightforward, but follow along to get the hang of it: Q: How many rows are there? A: The number of rows in the Global Table. Q: What columns with the table have? A: The same columns as in the Global Table. Q: How do you get the data for each cell? A: Given the row and column, look up the value in the Global Table For the Global List, things get a little more interesting: Q: How many rows are there? A: The number of entries on the list. Q: What columns with the table have? A: There is a value column, and there is a column for each field on the list. Q: How do you get the data for each cell? A: Remember that each row represents an entry on the list. For the value column, I get the value that was pushed on to the list to create the entry. For each field column, I get the value of the field for that entry. For example, suppose you have this list: Then supposed that you pushed a 5, 23, -12, 7, and 2 on to this list. When you view the entries on the list, you can see the data on this list laid out as a table: Notice that the value column has the values that were pushed on the list. The field columns (Doubled, Tripled, OddOrEven, and IsNegative) are each filled with the values of that field. The query() command has built-in support for Global Tables and Global Lists. However, it is always important to remember that to the query() command, the data is laid out in a table. If the data is not laid out in a table, you can still use the query() command, but you will need to use the methods explained in the Explicitly Defined Tables section. Basics - Queries SQL stands for Structured Query Language, so we can guess that it is a language for making queries. So what is a query? In a general sense, a query is a question. In SQL, a query is a question with two parts: who are you asking, and what do you want to know? There is a general answer to both parts of the question, and this is where tables come in. The answer to the first part (who are you asking?) is always a table. A SQL query is always directed at one (or more) tables. The answer to the second second part (what do you want to know?) is usually a new table. A SQL query takes in a table, and gives back a new table. The power in SQL comes from the new tables you can make. You can make a table that is a sorted version of the old table, like sorting data in excel. For example, if you have a list of items that need to be processed, you can sort that list by the item's priority. You can also make a table that is a filtered version of the old table, meaning you only kept certain rows. For example, if certain operators can only do certain tasks, you can make sure to only include the tasks that operator can do. In fact, you can make a table that is filtered, sorted, and modified in several other ways all with one query statement. Basics - Queries in FlexSim Let's look at examples of the query() command. You can follow along using the attached model ( numberlist.fsm). That model has a script that pushes values on to the list, and then queries the list. It also puts the result into the Global Table called QueryResult. Let's look at the line of that script with the query() command: int newTableRows = query("SELECT value FROM NumberList"); This line has a lot of new material. You can see that the query() command takes at least one argument, which is the text of a SQL query. We'll discuss the query itself in a moment. The query() command takes in the SQL query, and creates an internal (and invisible) temporary table that contains the result of the SQL query. It then returns the number of rows in the temporary table. Since you can't readily see the new table made by the query() command, you may want to copy the temporary table to a global table, using the dumpquery() command, as the script does: dumpquery(reftable("QueryResult"), 1); The temporary table lasts until you run the query() command again. Now for the query itself. You can see two parts of this query. The question "What do you want to know?" is answered by the SELECT statement. The question "Who are you asking?" is answered by the FROM clause. In this case, the FROM clause just lists one table, the NumberList. Recall that even though the NumberList isn't technically a table, you can visualize it's data as a table, which is what the query() command does (you can always right-click the NumberList in the Toolbox and choose the "View Entries" option to see the data as a table). In this example, the SELECT statement lists a column name. This means that the resulting table will have 1 column, because only one is required by the SELECT statement. When you run the script, it will put the result of the query in the QueryResult table: Notice that this table has only one column, the value column. If you look at the NumberList entries, you will see that this column is identical to the value column in that table. Examples To give you a general idea of what you can do with queries, these examples show a few common tasks. The examples all query the NumberList, which can be visualized as the following table: Selecting Multiple Columns SELECT value, IsNegative FROM NumberList Filtering SELECT value, IsNegative FROM NumberList WHERE IsNegative == 1 SELECT value, OddOrEven FROM NumberList WHERE value >= 5 Sorting SELECT value, Doubled FROM NumberList WHERE value >= 5 ORDER BY value Advanced - Callback Values It is often necessary to create a dynamic query. In FlexSim (not in regular SQL), you can do this by replacing a value in a query with a $n variable. This variable corresponds to additional parameters in the query() command. If you specify $1, then the value in the query will be the first additional parameter in the query() command, $2 will correspond to the second, and so on, up to $9. For example: query("SELECT Col1, Col2 FROM MyTable WHERE Col1 > $1 AND Col2 < $2", 10, 20) This query creates a table with Col1 and Col2, but only the rows where Col1 is greater than 10, and Col2 is less than 20. It is possible to include the values 10 and 20 in the query text. However, the $ variables allows you to easily change the value in the query, and replace them with more complicated expressions. Note that using callback values in a query where the FROM value is a Global List is not supported before versions 16.0.6/16.2.1. Advanced - Explicitly Defined Tables and the $iter() command Another FlexSim-specific feature of the query() command is the ability to explicitly define a table. This means you can query data that isn't arranged in the table format. In order to do so, you will need to answer the questions posed above, but shown again here: How many rows are there? What columns will the table have? How do you get the data for each cell? Once these questions are answered, the query() command can treat your data like a table. Each of the following subsections will answer these questions in detail. Defining the Number of Rows Let's start with a simple example: query("SELECT 1 FROM $1", 5) Notice that we are selecting from a number, not a Global Table or Global List. When the query() command sees a number instead of a table in the from statement, it assumes that you are querying a table with that number of rows. The statement above yields the following table (after a call to the dumpquery() command): This table has five rows, because $1 (the first additional parameter) evaluates to 5. All the rows have the value 1 because SELECT can handle expressions as well as column names (or expressions involving column names). Note that defining a table will only work if you use callback variables. A from statement like FROM 5 is not valid. To determine the number of rows in the table, use callback variables in the FROM statement. Defining the Columns To define the columns of your table, use the SELECT statement. Each expression in the SELECT statement will result in a column. When you are explicitly defining a table, you will often use callback variables as columns. This is where we can take advantage of the query() command. The query() command is very different from most other commands, because most commands only evaluate their parameters once. The query() command, however, can evaluate its parameters as many times as it needs to. Let's look at another example: query("SELECT $2 FROM $1", 5, normal(0, 1)) The result of this query is the following table: Notice that the second parameter, corresponding to $2, was re-evaluated as many times as the query needed it. Getting the Value in Each Cell Finally, we need a way to access the correct value for a given row and column. To do that, we need a way to know which row we are currently dealing with. This is where the $iter() command comes in. For example: query("SELECT $2 FROM $1", 5, $iter(1)) The $iter() command accepts an argument. That argument should match the value of the callback variable, e.g. if you used FROM $1, then the $iter() command should take a one as an argument. The $iter() command is linked to the query() command, so that its return value depends on which row is being evaluated. The above query results in the following table: Notice that $iter(1) returned the row number for each row. Now we can begin to query the tree, as if it were a table. Let's start with a simple example. Suppose you wanted a table of all the names of the first-level subnodes of the model tree. Let's start by answering the three questions: Q: How many rows are there? A: The number of first-level subnodes of the model Q: What columns with the table have? A: A column for the name of each of those subnodes Q: How do you get the data for each cell? A: Given the row number, get the name of that object Let's translate those answers into a query. First, we need to query something that isn't in table format already, so we know we need to use callback variables in the FROM statement: query("SELECT ... FROM $1", ..., ...) Next, we need a column for the names of all the subnodes, so we add one to the select statement: query("SELECT $2 FROM $1", ..., ...) Next, we need to answer the question of how many rows there are. Since this is the number of subnodes, you can write that as content(model()): query("SELECT $2 FROM $1", content(model()), ...) Finally, we need a way to get the name of each of the subnodes. We know that $iter(1) will give us the values from 1 to content(model()), so we can use those values in the rank() command, and we can pass the result of the rank() command to the getname() command: query("SELECT $2 FROM $1", content(model()), getname(rank(model(), $iter(1))) ) After dragging in a few random objects into the model, you can run that query. If you use the dumpquery() command, you can get a table like this: In the previous example, we used the value from $iter(1), and passed it in to rank(), and from rank() to getname(), all to get the name of the nth subnode of the model. Since querying a node in this way is fairly common, the query() command also allows you to specify a node as a table, rather than a number. In this case, $iter(1) will iterate over all the subnodes of $1, rather than the values 1 to $1. This makes our query much simpler: query("SELECT $2 FROM $1", model(), getname($iter(1))) Advanced - Flattening Data There is another option for what you can query in a FROM statement. If you use a callback variable (like $1) as your table, then you can use flattening syntax, shown in the following example: query("SELECT $3, $4 FROM $1x$2", 3, 2, $iter(1), $iter(2)) This query makes the following table: Notice that for every possible value of $1, there is a row for every possible value of $2. That is the purpose of the x (called the flattening operator); it ensures that there is a row for each permutation of all the callback variables involved. A query containing FROM $1x$2x$3x$4 would produce a table with enough rows for each unique combination of $iter(1), $iter(2), $iter(3), and $iter(4), and then execute the query on that table. The user manual contains an excellent example of when flattening syntax might be helpful, shown in the help manual in Miscellaneous Concepts > SQL Queries > Example.
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Introduction   A new feature-version of FlexSim Simulation Software is released several times per year. In order for client PCs to be able to run a licensed version of the upgraded software, you may need to upgrade the activated license(s) on your license server. Licenses with a current maintenance subscription are eligible to be upgraded to the latest version.   If you don't understand how licensing works for different FlexSim versions, please review our Answers article FlexSim Version Numbering.   Overview   There are 6 main steps to upgrading the licenses hosted on your lmadmin or lmtools license server:   Check if you need to upgrade your license server files Return the licenses you intend to upgrade Upgrade your licenses Activate the upgraded license Reread the license Upgrade client PCs   Several of these steps have their own fully documented procedures. We'll link you to those resources below.   1. Check if you need to upgrade your license server files   If your organization's license server was installed previously and hosting licenses for FlexSim 25.1 or lower, it may need to be upgraded for compatibility with FlexSim 25.2 and higher. Click here to learn more or go directly to the latest license server files.   After you have upgraded your license server files, move on with the rest of the upgrade process, as outlined below.   2. Return the licenses you intend to upgrade   The steps to return a license-server-based license are fully documented. Choose the link below that best matches your needs, depending on whether your license server can connect to the Internet:   License Server - Return - Online License Server - Return - XML / Offline   Be sure to return ALL licenses you wish to upgrade.   3. Upgrade your licenses   NOTE: Licenses with expired maintenance will not upgrade. Timed licenses do not upgrade. Only permanent (not timed) licenses under current maintenance can be upgraded. Contact your salesperson for extending a subscription or other circumstances.   Log in to your FlexSim Account.   If you were already logged in to your FlexSim Account, in the top navigation menu hover over your initials icon and choose Reload Account.     Now in the top navigation menu, choose Licenses > List.     Check that the available seat count is equal to the total. All of a license’s seats should be returned for it to upgrade.   Click on the Upgrade Licenses button.     If you have several licenses to upgrade and all are owned by or shared with your FlexSim Account, they will all be upgraded at once. Please be patient while the upgrade process works in the background.   When the page refreshes, eligible licenses will have a new activation ID for the latest version of the software. Your license code indicates its version at the end of the code to help you know what versions your license will properly activate. Review license code format.   4. Activate the upgraded licenses   The steps to activate a license-server-based license are fully documented. Choose the link below that best matches your needs, depending on whether your license server can connect to the Internet:   License Server - Activation - Online License Server - Activation - XML / Offline   5. Reread the license   Your license server needs to start serving up your newly activated licenses. You can either restart your license manager service, or use your license manager's option to reread your licenses.   The steps to reread your licenses differ depending on which license manager you are using to host your licenses. Use these links to jump to instructions for the license manager you're using:   lmadmin lmtools+lmgrd   6. Upgrade client PCs   Finally, upgrade your PC with a version of FlexSim appropriate for your new license (learn how licenses work across versions).   After installing a new version of FlexSim, you will need to configure it to get a license from your license server. There are two ways a client PC can be configured. Choose the method below that most closely matches the main use case for your client PC:   Single-user client PCs - this method configures settings that are saved on a per-user basis. Multi-user client PCs - usually appropriate for a university computer lab or other shared-PC situation, where the configuration should be computer-based.   Having trouble licensing your client PC?   Verify client PC licensing to find out if your client PC is successfully getting a license from your new license server. Diagnose Client/Server connectivity issues that may be preventing your FlexSim software from obtaining a license. Discover other issues that may be preventing your client PC from obtaining a license by working through our License Server Troubleshooting tips.  
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