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Hi Emily,
Please double check that any transition group that shows up in your Transition Target datasheet should either be appended with the text “[Type]”, or if not, it should be defined as a transition simulation group under “File | Project Properties | Transitions | Advanced | Transition Simulation Groups”. If you only have Transition Groups appended with [Type] in your Transition Targets, you should double check that none of these are defined as belonging to a Transition Simulation Group under “File | Project Properties | Transitions | Transition Types by Group”.
Regards,
LeonardoHi Shulhan,
I suspect there are two possible reasons for the problem with initial conditions. Is this a network drive that perhaps has restricted permissions and is not allowing SyncroSim to create a folder here? It is also possible that the path is too long. I would try to put your library in a different location.
You are right about there being no fixed rule for determining transition probabilities. The method you use will depend on the questions and model, as well as on the available data. I recommend you read through some of the published examples (https://docs.stsim.net/publications.html) to see the different approaches people have taken.
Regards,
LeonardoThere are many possible reasons why this might happen. Could you give us a bit more information about your scenario settings? Perhaps list the datasheets that are specified for your scenario. In version 2.2 this is under the final tab in the scenario properties. In version 2.3 it is in the final node of the General tab (first tab). You should check that you have non-zero probabilities for your transitions and that the states where pathways are defined are actually occurring on your landscape.
It looks like for some reason SyncroSim can’t connect to the package server and you have no packages installed. Possibly a firewall or administrative priviledges issue? A possible workaround would be to manually download the packages you need and install them from file. For example, for ST-Sim you would do the following:
1. Download a package release that is compatible with your version of SyncroSim. For ST-Sim I would recommend version 3.2.28, the stsim-3-2-28.ssimpkg file is available here: https://github.com/ApexRMS/stsim/releases/tag/3.2.28
2. In SyncroSim go to “File | Packages” and select “Install from File” from the upper right hand corner of the window. Point to the stsim-3-2-28.ssimpkg file that you downloaded in step 1 and click “Open”.
3. Try doing a “File | New Library…” and you should be able to create a new ST-Sim library.Can you tell me a bit more information about the steps to get the error? Are you trying to create a new library in the Window’s interface using “File | New”? Can you tell me what package are you trying to build a library for? Is this an ST-Sim library you are trying to build? Also if you go to “File | Packages” what packages and versions are listed?
Hi Kevin,
I have not experienced this error recently. However, I did update the AWS instance to a more recent 2019 Microsoft Windows Server. What operating system and .Net Framework version are you running? Are you able to run the model on a local machine but not on your server?To check what versions of .Net you have installed you can run the following line of code in Windows Powershell ISE:
Get-ChildItem ‘HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP’ -Recurse | Get-ItemProperty -Name version -EA 0 | Where { $_.PSChildName -Match ‘^(?!S)\p{L}’} | Select PSChildName, versionYou should then get some output that looks like this:
PSChildName Version
———– ——-
v2.0.50727 2.0.50727.4927
v3.0 3.0.30729.4926
Windows Communication Foundation 3.0.4506.4926
Windows Presentation Foundation 3.0.6920.4902
v3.5 3.5.30729.4926
Client 4.8.03752
Full 4.8.03752
Client 4.0.0.0
________________________________________Cheers,
LeonardoHi Kevin,
I have not experienced this error recently. However, I did update the AWS instance to a more recent 2019 Microsoft Windows Server. What operating system and .Net Framework version are you running? Are you able to run the model on a local machine but not on your server?To check what versions of .Net you have installed you can run the following line of code in Windows Powershell ISE:
Get-ChildItem ‘HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP’ -Recurse | Get-ItemProperty -Name version -EA 0 | Where { $_.PSChildName -Match ‘^(?!S)\p{L}’} | Select PSChildName, versionYou should then get some output that looks like this:
PSChildName Version
———– ——-
v2.0.50727 2.0.50727.4927
v3.0 3.0.30729.4926
Windows Communication Foundation 3.0.4506.4926
Windows Presentation Foundation 3.0.6920.4902
v3.5 3.5.30729.4926
Client 4.8.03752
Full 4.8.03752
Client 4.0.0.0
________________________________________Cheers,
LeonardoHi Louis,
If your initial conditions are for 2010, then yes, you are correct that you do not need to start setting inputs for transition multipliers until 2011, no transitions will take place for the 2010 timestep.For Run Control, your Start year should be set to 2010. This represents Timestep 0 which is not simulated.
Transitions will begin to be simulated for the next timestep, in your case 2011. If you then view state outputs for your model for 2010, they should exactly match your initial conditions.Regards,
LeonardoHi Miles,
Could you clarify your question a bit:
1. Are you seeing more randomness than you would expect in your initial state distribution?
2. Less randomness than you would expect?Unless you select the checkbox to “Calculate from distribution” checkbox, the model interprets your inputs for initial conditions as a frequency distribution so you should see some randomness in your initial conditions. The more cells that you run (i.e., the larger the population you are sampling from), the closer that your simulated initial conditions will match your input values.
If you choose to “Calculate from distribution” for the number of cells, your initial conditions will be deterministic allocating the value in the “Relative Amount” field to be the number of cells corresponding to each record. You can find out more in the documentation for this property.
Hi Luke,
Good question. The answer to a large part depends on what computing resources you have available to you. We do many of our simulations using cloud computing resources such as AWS EC2 virtual servers. Using these servers, it is not unreasonable to do simulations with landscapes encompassing 1-10 million cells for multiple decade runs with 100 Monte Carlo realizations. The most extreme example we are currently working on is running landscapes >100 million cells. In this case we require machines with large amounts of RAM >64GB and also make use of spatial multiprocessing to run independent landscape units. In this case it can take a few hours (3-10) to run a single timestep/realization. SyncroSim can also run in a Linux HPC environment and there are some published examples of that on the ST-Sim publications page. See for example Sleeter et al. 2019.For the example you provide your rasters would look like this:
Timestep 1, Fire, Fire-Spatial-Multipliers-ts1.tif
1.0 0.0
0.0 1.0Timestep 2, Fire, Fire-Spatial-Multipliers-ts2.tif
0.0 1.0
0.0 0.0Timestep 3, Fire, Fire-Spatial-Multipliers-ts3.tif
0.0 0.0
1.0 1.0Hi Luke,
Yes. You can be prescriptive about which cell receives a transition at which timestep. Here are the steps I would follow.
- Identify which transitions are going to be specified using prescriptive instructions for each cell with a spatial time series.
- For the prescriptive transitions identified in #1, set the base probability in the Transition Pathways to a value of 1.0
- Under the scenario property Advanced | Transitions – Spatial | Transition Spatial Multipliers enter rows for the Transition Types/Groups that you would like to specify a spatial raster that identifies for which cells the transitions occur. Note that you can right click on the table to expose the Timestep field and make the raster time varying. Cells with a value of 1.0 will have the transition applied to them in that timestep. Cells with a value of 0.0 will not have the transition occur. A value between 0.0 and 1.0 can be used to set a probability for a specific cell and timestep.
- Each raster will be applied starting in the timestep that it is specified until the next timestep that another raster is specified so you must remember that if you turn a cell on in one timestep, you must turn off the cell in subsequent timesteps when you no longer want a transition to occur.
- Transition Spatial Multiplier rasters must have the same number of rows and columns as your Spatial Initial Conditions rasters.
Hi Kevin,
If your cost/distance raster is static or defined temporally but independent from the model, you could use it to generate Transition Spatial Multipliers (http://docs.stsim.net/reference/prop_transition_spatial_mults.html) to set the probability of transitions for each cell.
If you would like to build in some feedback between modeled landscape dynamics and your cost/distance raster, you may be able to use the Transition Adjacency Multipliers feature found in ST-Sim (http://docs.stsim.net/reference/prop_transition_adjacency_mults.html). This is an advanced feature that allows you to change transition probabilities as a function of the state of cells within a neighborhood. So for example you could set the probability of an urban growth transition to be 0 when it has no urban neighbors within a 500m radius and increase this probability as a function of the number of urban neighbors within that radius.
As a follow-up to this post I would like to point out that releases of ST-Sim 3.2.18 and later now have additional options for applying TST. In fact the above can be more easily accomplished by adding two records to the “Advanced | Transition – Multipliers” Scenario property.
The first record would specify:
TST Type/Group: Fire [Type]; TST Min: 0; TST Max: 19; Transition Type/Group: Fire [Type]; Multiplier: 0.
The second record would specify:
TST Type/Group: Fire [Type]; TST Min: 20; TST Max: [BLANK]; Transition Type/Group: Fire [Type]; Multiplier: 1.In this single screen you are now specifying that the probability of a fire occurring within 20 timesteps of a previous fire on the same pixel is multiplied by zero whereas after 20 timesteps have elapsed the probability is multiplied by one.
Hi Kori,
It looks like there are some absolute paths in your library that are coded to specific folders. A first try would be to go to File | Library Properties and open the Folders tab. In here I would Clear all of the folders. If you are still having trouble charting after this I would open the path to where your library is located and delete the folder called [LibraryName].ssim.temp.
Let me know if that helps.
Leonardo
