GMS

Switching Model Executables

The Groundwater Modeling System, Surface-water Modeling System, and Watershed Modeling System (collectively known as XMS) applications make use of multiple numerical models. XMS is packaged with the executables for each of these numerical models. At times, you may need to switch out which numerical model executable XMS uses.

In general, you will want to use the model executable that comes packaged with the XMS. XMS is coded to work with the specific model executables that are distributed with each version of the software.

There are some reasons you might want to change which model executable it used. It might fix a bug with the model executable. It might get you access to features in an older or newer version of the model executable. It might also help you test issues with the numerical model. Replacing the model executable isn't guaranteed to help with any of these, but it is one option for troubleshooting with all of them.

For all XMS applications, the numerical model executables to be used are selected in the Preferences dialog. If you already know where the model executable is, you can copy and paste the executable into the preferences dialog. To do so, use the following workflow:

  1. Copy the executable file path. If using Windows 11, right-click on the desired model executable and select "Copy as Path."
  2. If using Windows 10, open the Properties dialog from the right-click menu. Copy and paste the location path into a text document. Then, make sure to grab the file name ending in ".exe" as well. The executable path will be incomplete without that file name.
  3. In your XMS software, open the Preferences dialog from the Edit menu.
  4. Find the model executable that you want to change and click on the file path next to the name or the Browse button.
  5. In SMS or WMS, this will bring up an Open dialog. In the File name box, paste in the new executable path. If you are using Windows 11, make sure to delete the quotation marks at the beginning and end. Selecting Open saves the new model executable.
  6. In GMS, the model executable is editable without bringing up the Open dialog. Simply erase the former executable path and paste in the new one. As long as the path is a valid path and the path ends in ".exe", GMS will save it. Again, for Windows 11, delete the quotation marks.
  7. Finalize the model executable by clicking OK to exit the Preferences dialog. Otherwise, the executable will not save.
Example of model executables in the Preferences dialog

Now, there are some issues to keep in mind. As mentioned earlier, changing out a numerical model executable is not guaranteed to fix a particular issue or even improve the situation. Older or newer versions of the model executable may not always be compatible with your version of XMS. Sometimes the model executable is not compatible with a particular project. The new executable might even worsen the situation. If any of these things happen, you can reintroduce the original executable.

Check out the available model executables in XMS today!

Blog tags: 

Creating UGrid Cross Sections in GMS

GMS 10.7 has added functionality for creating and viewing cross sections on unstructured grids (UGrids) in your GMS project. This article discusses this added functionality for creating UGrid cross sections and some things to keep in mind while using it.

You can use it anytime you want a quick view of the inside of a UGrid. Perhaps you want to review the contours of a MODFLOW 6 dataset or the materials in a specific section of a UGrid. With the Create Cross Section tool, you can quickly create a cross section that visualizes these values.

To use this tool, go to the UGrid Module in GMS and select the tool called Create Cross Section. Then, click out a line across your 3D UGrid in the GMS Graphics Window. This creates a new UGrid cross section, and a new cross section item appears in the Project Explorer under the active UGrid.

UGrid Cross Sections in GMS

Depending on the display options you choose, it may be necessary to hide the UGrid to see the cross section you created. You can hide the UGrid by clicking the checkbox next to it in the Project Explorer. Even though the cross section is categorized under the UGrid in the Project Explorer, the cross section does not disappear when the UGrid is hidden. Another option for visualizing the cross section is to turn off face contours and cell faces in the display options for the active UGrid.

Regardless of the length of the line you click out, the Create Cross Section tool will create a cross section along your line from one end of the UGrid to the other. This tool does not create partial cross sections.

Moreover, this tool only creates cross sections on the active UGrid, even if other UGrids are visible and the active UGrid is not. Every UGrid cross section drawn is saved under the currently active UGrid in the Project Explorer.

If you accidentally create a cross section, it can be easily deleted by selecting it and using the delete command. This also allows you to create a UGrid cross section to quickly verify something, but then delete it just as quickly. It does not show up in your final model if you don't want it to.

These cross sections have a separate display options dialog that is accessed individually by right-clicking on the cross section in the Project Explorer. In the display options, the elevation offset for the UGrid cross section can be set. This allows for the cross section to appear above the UGrid for viewing. There are also options that allow you to decide which dataset the cross section contours represent. Many of the options relating to things like contours and cells are accessed by clicking the button labeled Other Display Options.

Creating UGrid cross sections makes visualizing 3D UGrid data more straightforward than before. Try the Create Cross Section tool in GMS 10.7 today!

Blog tags: 

Transferring Data between GMS and ArcGIS Pro

Exporting and importing data between ArcGIS Pro and GMS allows many users to improve the quality of their groundwater models. Today we explore moving data between these two applications, focusing mostly on shapefiles.

Exporting and importing shapefiles allows features that have already been digitized in one program to be transferred to another program. For instance, once data has been modeled in GMS, it can be converted to a shapefile and imported into ArcGIS Pro. Furthermore, feature objects that have already been drawn in ArcGIS Pro or GMS can be transferred to the other program and then used as feature objects for the work you’re doing there.

To start, consider exporting feature objects from GMS as a shapefile. You can draw arcs in a coverage and then use the right-click menu in the Project Explorer to export the information. There are three options for file type, so make sure to select "Shapefile (*.shp)" from the Save as type drop-down. Once you click Save in the Export Coverage dialog, another dialog opens that allows you to choose what kinds of shapefiles you want to save. There are arc, point, and polygon shapefiles. Once you've exported the shapefiles, they can be imported into ArcGIS Pro using that program’s Add Data function on the Map ribbon tab.

Exporting a shapefile from GMS

It's important to keep in mind that when GMS feature objects get exported to a shapefile, there are a couple of other file types that get exported with them. It's important to keep all of the files together because the shapefile is not complete without those other files. For example, one of the file types has projection information that lets other GIS programs, like ArcGIS Pro, know where the shapefile is located geographically. Without it, the shapefile is not attached to specific geographic coordinates, making it far less useful. You might consider putting all the files created in the shapefile together in a folder. This could help keep them together if you choose to relocate them after creating them.

GMS also allows for exporting of contour features and MODPATH particle tracking lines as shapefiles. However, these shapefiles do not appear when they are imported into ArcGIS Pro. Fortunately, there is a workaround for this issue. The shapefiles that GMS creates can be imported back into GMS after being exported. Then you can convert them to feature objects. Once they are converted to feature objects, you can use the same process described above to turn them into shapefiles that ArcGIS Pro can visualize.

GMS also has the ability to import shapefiles created or edited in ArcGIS Pro. Points, arcs, or polygons can be created in GMS, exported to ArcGIS Pro, edited in ArcGIS Pro, then saved and subsequently imported back into GMS. ArcGIS Pro also has exporting tools that can create shapefiles, CAD data, or other types of data for GMS to import.

There are other kinds of information that can be exported and imported between the two programs. Both programs have means for exporting and importing text files; 2D UGrids and other geometries in GMS can be exported as shapefiles; Rasters, scatter datasets, and other forms of data can also be transferred between GMS and ArcGIS Pro. In short, importing and exporting between these two programs has many possibilities.

Explore exporting and importing tools in GMS today!

Blog tags: 

Using Layer Range Options in GMS

The conceptual model approach in GMS is a very useful way to assign specific attributes to a MODFLOW model without having to manually input them cell by cell. One particularly helpful tool available in a GMS coverage is the "Layer Range" option.

Example of the Coverage Setup for Layer Ranges

Layer range can be used in addition to other coverage choices—such as streams, wells, rivers, head boundary, etc.—allowing you to be as precise as you need to be when applying your model attributes.

In the past, we have mentioned this tool in a blog post about assigning Ugrid attributes to specific layers, but that is only one of many helpful ways to use it. Here, we will go over each of the options available with the Layer Range, and exactly how they work.

First, turn on this option by selecting "Layer Range" in the sources/sinks column of the coverage setup dialog. At the bottom of this dialog, make sure that the default layer range for the coverage covers all the parts of your grid that you wish to use.

Second, apply feature objects to your coverage. In our example, we have created a Time-Variant Specified Head arc.

Example of the Layer Range Assignment in GMS

Once your feature objects are in place, you can assign values to them in the attribute table. This is where the Layer Range settings will come into play.

  • Use Layer Range: This option applies your feature objects to a specific range of layers. That range is selected in the attribute table under "From Layer" and "To Layer". A feature point assigned a layer range of 2–6 will be applied to every cell in that vertical column from layer 2 to layer 6.
    Similarly, a polygon or arc will apply its attributes to the whole assigned layer range for every vertical column that it intersects.
  • Auto-Assign BC to One Cell: Any time you want only one cell per column, you can choose "Auto-Assign BC to One Cell". This setting is especially useful when mapping an object type that can't or shouldn't be applied to more than one vertical cell at a time. Stream arcs are one example.
    Auto-assigning to one cell will use the elevation inputs from your feature object to choose the most applicable cell in that vertical column to receive the assigned attributes.
  • Auto-Assign BC Including Lower Cells: This setting allows the coverage to automatically calculate which initial layer the object is applicable to, similar to the "One Cell" option. It then applies the object to that cell, and to everything below it within the range of the coverage.
    Including the lower cells is very useful when you do want more than one vertical cell to be assigned, but need different layer ranges for different parts of the same feature object.

Once you have selected the Layer Range option that best suits your model, you can map the coverage to your simulation. The results can be viewed in the MODFLOW | Optional Packages dialogs, as well as the Sources/Sinks table in the right-click menu for the grid cells.

The Layer Range tool is a great way to get your model attributes as specific as you need them to be without any laborious manual editing. Try it out in your GMS model today.

Blog tags: 

Pages