Automating HEC-RAS with Excel
8 likes6,183 views
This document presents an overview of automating HEC-RAS using Excel, highlighting the HEC-RAS capabilities and the HEC-RAS Controller API for external manipulation. It includes basic programming demonstrations in Excel VBA for multi-model runs and output extraction, along with tips and potential challenges of using the API. The author concludes that while the API offers significant functionality, it requires effort to navigate due to inconsistencies and a lack of official documentation.
![2. The HECRASController API (cont’d)
The HECRASController API
“The current version of the HECRASController has a wealth of
procedures that will allow a programmer to manipulate HEC-RAS
externally by setting input data, retrieving input or output data, and
performing common [HEC-RAS] functions…”
- Christopher Goodell, PE, D.WRE, Breaking the HEC-RAS Code, 2014
5
HEC-RAS
Excel
API](https://image.slidesharecdn.com/automatinghecraswithexcel-150311105228-conversion-gate01/85/Automating-HEC-RAS-with-Excel-5-320.jpg)
Automating HEC-RAS with Excel
- 1. Automating HEC-RAS with Excel Virginia Lakes and Watersheds Conference, March 2015 Thomas Williams, PE Amec Foster Wheeler + = ?
- 2. Contents 1. What is HEC-RAS? (brief intro) 2. The HECRASController API 3. Excel VBA Demos 1. Multi-Model Run 2. RAS Output Extraction 3. Manning’s ‘n’ Calibration (sort of) 4. Tips 5. Conclusion 2
- 3. 1. What is HEC-RAS? 3 Hydrologic Engineering Centers River Analysis System “HEC-RAS allows you to perform one-dimensional steady flow, unsteady flow, sediment transport/mobile bed computations, and water temperature modeling.” - USACE
- 4. What is an API? API = Application Programmer Interface “In computer programming, an application programmer interface (API) is a set of routines, protocols, and tools for building software applications. An API expresses a software component in terms of its operations, inputs, outputs, and underlying types.” - Wikipedia 2. The HECRASController API 4 Their Program Your Program API
- 5. 2. The HECRASController API (cont’d) The HECRASController API “The current version of the HECRASController has a wealth of procedures that will allow a programmer to manipulate HEC-RAS externally by setting input data, retrieving input or output data, and performing common [HEC-RAS] functions…” - Christopher Goodell, PE, D.WRE, Breaking the HEC-RAS Code, 2014 5 HEC-RAS Excel API
- 6. 2. The HECRASController API (cont’d) Accessing the API from Microsoft Excel 1. Click the Visual Basic button (on the Developer tab) 2. Create a new VBA module 3. Go to Tools > References, check “HEC River Analysis System”, and click OK. 4. Write code! 6
- 7. 2. The HECRASController API (cont’d) A simple program… 7 Sub RunHECRAS() ' Opens and runs a HEC-RAS model ' Declare variables Dim ras As New HECRASController Dim nmsg As Long Dim strMessages() As String Dim prjFilePath As String ' Open the model prjFilePath = "C:MyHecRasModel.prj" ras.Project_Open (prjFilePath) ' Run the model ras.Compute_CurrentPlan nmsg, strMessages End Sub
- 8. 2. The HECRASController API (cont’d) Some example HECRASController fuctions and subroutines: • Project_Open Opens a HEC-RAS model. • Compute_CurrentPlan Runs the current flow/geometry regime. • ExportGIS Exports an *.sdf file that can be read into ArcGIS using HEC- GeoRAS. • Output_NodeOutput Returns an output value for a given node and profile. 8 • Geometry_SetMann Sets the Manning’s ‘n’ values for a cross section, horizontally varied. • Add_BC Adds a bridge/culvert. • Edit_BC Opens the Bridge/Culvert Editor and displays the selected station. • PlotPF Displays the water surface profile for a given River/Reach.
- 9. 3. Excel VBA Demos 9 1. Multi-Model Run 2. RAS Output Extraction 3. Manning’s ‘n’ Calibration (sort of) Cross your fingers!
- 10. 4. Tips • Breaking the HEC-RAS Code by Christopher Goodell, PE, D.WRE • The API is a little rough around the edges. • Provides a lot of functionality, but not everything • Inconsistencies: • Parameter names and types • Function / subroutine behavior • No “official” API documentation • HEC-RAS is public domain software, but not open source • HEC-RAS project (*.prj), geometry (*.g##), flow (*.f##), and plan (*.p##) files are plain text. • Sometimes that’s easier than using the API. • HEC-RAS output files (*.O##) are binary. 10
- 11. 5. Conclusion 1. The HECRASController API is really useful… 2. …but it takes a little work to figure out. 3. Happy coding! Questions? Contact Info Thomas Williams, PE Amec Foster Wheeler thomas.williams@amecfw.com 11