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Hi Jessica, in order for us to help you with this particular situation we would need you to submit a support request. Please go to http://www.apexrms.com/support for further details on how to do so.
Cheers,
LeonardoHi Agnes,
The most likely cause for this error is a bug in Version 3.1 related to the new spatial functionality. To work around this bug go to the Run Control tab of the scenario properties. Select the ‘Run Model Spatially’ checkbox and save your project. Then uncheck this box and save your project again. This bug was fixed in version 4 of Path. Let me know if this does not resolve your problem.
Cheers,
LeonardoIt looks like you are trying to join records from DisturbedPolygonOutput and StateOutput tables in the TELSA database to LUPolygonID in your LUMap. This is not the correct join for output. To view output you need to join from the ScenarioPolygonID field in the output table to the ScenarioPolygon.ScenarioPolygonID field and from there find the corresponding ScenarioPolygon.PolygonID. This is the value that you will need to join to the PolygonID field in your tessellated Study Area Map. The number of records in StateOutput should match the number of records in your tessellated map. You can find the shp file for your tessellated Study Area map by looking in StudyArea.SpatialFile in the database.
Hi Ayn,
Path 4.0.10 no longer runs VDDT as the simulation engine and so it does not read MCM files. To use temporal multipliers you need to use the Transition Multiplier Property on the Advanced Scenario Property tab. Using this property you can specify transition multipliers by stratum, iteration, timestep, and transition type. The first three of these inputs are optional and if left blank will apply to all possible cases.
Cheers,
LeonardoHi Alison,
This error happens because when opening the spatial tools you need to point to the results database. In your case this is:
C:\Documents and Settings\areger\My Documents\My Path Files\Scenario-10\Scenario-10.mdbAt this stage the documentation for the Spatial Tools is quite thin because we have had very little funding to date for the development of the spatial tools functionality.
To view map results you should select the Map Display button on the TELSA Toolbar in ArcGIS. You will then be prompted to select a results database if you have not already done so. Once you select the database that holds your TELSA run results you will be prompted to select a run, monte carlo, and the type of map you would like to display. There are currently 3 options: Disturbances (transitions), State Classes, and Ages. Depending on the option you choose you will be prompted for more information (which state classes or transitions you would like to display). Note that this tool is not always stable. If you are having problems, try closing ArcGIS and starting over.
Cheers,
LeonardoIn version 4 we changed the database schema so the CEAGeneral Table which specified resolution and total area has been changed to the RunControl table which specifies number of simulation cells and total area. I imagine that the “GIP tool” will need to be modified to work with this schema. Note that if you are entering data directly into the database without the UI there is currently no validation rule on the number of simulation cells so you want to be careful about entering a value >=1.
Hi Jessica,
The reason for this crash is because for your TELSA template database for this landscape you have loaded the LU Map and run the tessellation but have not yet run the spatial scenario setup. Please refer to this post: http://www.apexrms.com/content/path-and-telsa
It looks like you have missed step 5. Run the spatial scenario setup using the TELSA spatial tools without specifying a planning zone map or operational unit and then try to run the simulation again. Let me know if that works for you.
The warnings are unrelated to this crash. They are happening because your time since transition groups property for this scenario specifies time since transition groups for each stratum. In TELSA, time since transition groups are global and can’t be specified by stratum so the warning is telling you that for Alt succession the time since transition group used will be the one specified for stratum ‘Boreal_Spruce_Fir_Hardwood_CNTY’ and for Replacement fire the time since transition group used will be the one specified for stratum ‘Acid_Peatland_Systems_CNTY’. I don’t think this is a problem because in your case the time since transition group is always ‘All Fire’ regardless of the stratum.
Cheers,
LeonardoHi Jessica,
Please post your database to the ESSA FTP site:
ftp://ftp.essa.com/incoming/and I’ll have a look.
Cheers,
LeonardoThanks for posting your database. In your specific case the issue was caused by the following:
In version 3 of Path which you are currently running, the number of simulation cells to run is calculated as the total area set by the user in ac divided by the resolution set by the user. Your model uses a resolution of 200*200 m or roughly 10 ac. The number of simulation cells is calculated as an integer so anything less than 5 ac in size will have a calculated number of simulation cells of zero and will result in the message you describe.
In Path version 4 the user sets the total area and the number of cells rather than the resolution. The user interface will not allow you to set the number cells to a value less than 1 so you should not encounter this problem. In the current beta release of version 4, when you upgrade your data from the previous version it will calculate the number of simulation cells based on the formula described above and you may end up with scenarios with zero simulation cells. This is something we will fix in the full release of version 4.
To better understand the problem you are experiencing, it would be helpful for me to know what version of Path you are running and to get a copy of the database you are using. Would you be able to post it to ESSA’s incomming FTP directory (ftp://ftp.essa.com/incoming/) and let me know when it is uploaded?
It could be that your strata are so small that the number of simulation cells being assigned to them is equal to zero. This would happen if the proportion of the total area made up of that stratum multiplied by the total number of cells being used for the simulation is less than 1. Note that this should no longer be a problem in the upcoming version 4.0 of Path that has it’s own simulation engine, rather than relying on VDDT.
Cheers,
LeonardoYou are right that there are no planning zones in Path. This means that if you have planning zones you will need to use the stratum feature to define them. Each stratum will consist of the combination of planning zone and the ecological stratification. So for example your ecological stratification might include (1) Ponderosa Pine and (2) Mixed conifer and your planning zones might include (a) National Forest and (b) Private. In Path you would define the 4 strata that represent all possible combinations of these. You would then define a model for each stratum and be able to also specify management targets for each of these. This may seem like an onerous process but remember that in Path it is quite easy to copy an entire model and paste it into another stratum using the transition editor.
One of the main objectives in developing Path was to have a single integrated environment for simulating State and Transition Simulation Models either spatially or non spatially. For non-spatial models we have completed this goal but for spatially explicit models we are not quite there (yet). Path now has the ability to run the TELSA C++ model as a spatially explicit simulation engine. We have tried to minimize the amount of interaction between the user and the old TELSA user interface but given resource limitations there is still one step that requires the user to interact with the ArcGIS TELSA spatial tools. This requires that the user works with both a Path and a TELSA Database. Here is a brief description of the relationship between the databases:
1. Users now define all definitions and non-spatial model rules in Path
2. At any point in time, users export these definitions to a template TELSA database and use the TELSA Spatial Tools in ArcGIS to import spatial map inputs into this database. This process is generally required only once per landscape.
3. Once the TELSA template with maps has been created the user can store this database and point to it in Path.
4. Whenever a scenario is run from Path as a spatially explicit model, Path creates a copy of the TELSA template database adds additional inputs specific to that scenario and calls the TELSA.exe C++ simulation engine to run that scenario. The non spatial outputs of the simulation are imported automatically to the Path database. The spatial outputs are stored in the copied TELSA database. By default the TELSA “run” database is stored in My Path Files | Scenario.
5. Because spatially explicit outputs are stored in the copied TELSA database, users interact with this database through the ArcGIS TELSA spatial tools in order to view maps of output.
Question 1 – How can the probability for each management transition be calculated given our information at hand (area of each cover type in each planning zone [area of each strata] and total area in a single planning zone to which an activity can be applied)?
Answer: As you have done using TELSA, you can choose to use Area Limits (called Transition Targets in Path) to define how much area is affected by a particular management activity during each timestep. Transition targets can be set by transition group and are optional for each transition group. If you choose not to use transition targets you can instead set the probability by deciding what proportion of the total area eligible for the activity you would like to happen during each timestep. In this case the absolute amount of area undergoing the transition will vary over time as the eligible area will also likeley vary.
Question 2 – Under the “Advanced” tab, do size distributions limit transitions similarly to assigning activity group limits in TELSA (step 3 above) or is this where we specify the size range for particular management activities as when setting up management systems in TELSA (step 2b above)? How is the information in the “Relative Amount” column used?
Answer: This is where you set the size frequency distributions for both management activities and natural transitions and it only applies when you are running the model spatially. Note that for spatially explicit simulations, transition groups must have a size distribution defined to be simulated.
To Simulate Path Models Spatially Using TELSA you need to take the following Steps:
1. Ensure that your definitions are compatible with TELSA. To do this, you need to make sure the each transition type belongs to only one transition group.
2. Export Your Definitions to a TELSA Template DB This is done using the “File | Export Definitions to TELSA…” menu. Keep track of the file and location of the mdb that you export your definitions to as you will need these for the next step.
3. Load your maps into the TELSA DB you exported your Path Definitions to in Step 2. Using the TELSA spatial tools (http://essa.com/tools/telsa/download/) you will load your LU Map into the mdb file from step 2. To do this, select the Map Library button from the TELSA Toolbar in ArcGIS and Add a Landscape Unit Map.
4. Tessellate your map using the TELSA Spatial Tools. To do this, select the Map Library button from the TELSA Toolbar in ArcGIS and Add a Tessellated Map.
5. Add Spatial Scenario To do this, select the Spatial Scenario button from the TELSA Toolbar in ArcGIS and click Add. Choose the tessellated map you just added but do not select either an operational unit map or a planning zone map.
6. Point Path to the TELSA database you just loaded your maps into. Return to Path and for the scenario you want to run using TELSA, open up the scenario editor and go to the Advanced tab. Select TELSA | Path TELSA Database and point to the database you just loaded your maps into.
7. Define your transition size distribution for each transition group using the TELSA | Transition Size Distribution property.
8. In the Run Control property choose to run your model spatially.
9. Under the Advanced | Output Options property select Detailed Output for timesteps that you want to create maps of state classes or transitions. Select Summary Output for timesteps that you want to graph.
10.Run the model
11. View Output. Graph outputs can be viewed just as with a non-spatial run. To view maps, go to the output folder (set under File | Preferences | General. There will be a folder with the Scenario ID you just ran. Inside that folder there will be a TELSA mdb file. Open up ArcGIS and use the TELSA spatial tools to point to your output TELSA mdb and view maps of state classes or transitions using the Map Display button on the TELSA toolbar in ArcGIS.
