API Reference

This section provides documentation for the RAS Commander Python API.

Core Classes

Primary classes for project management and execution:

• RasPrj - Project management and data structures
• RasCmdr - Plan execution (single, parallel, sequential)
• RasPlan - Plan file operations
• RasFlowOptimization - Native HEC-RAS flow hydrograph optimization settings and trial results
• RasGeo - Geometry file operations
• RasUnsteady - Unsteady flow file management
• RasSteady - Steady flow file authoring and parsing
• RasUtils - Utility functions
• RasExamples - Example project management
• RasMap - RASMapper configuration, layer discovery, and geometry HDF associations
• RasProcess - RasProcess.exe CLI automation, stored maps, and native reference validators
• RasControl - Legacy COM interface

HDF Modules

Classes for reading HDF result files:

• HdfBase - Core HDF operations
• HdfPlan - Plan information
• HdfMesh - Mesh geometry
• HdfResultsMesh - 2D mesh results
• HdfResultsPlan - Plan-level results
• HdfResultsXsec - 1D cross-section results
• HdfStruc - Structure data
• HdfResultsBreach - Dam breach results
• HdfHydraulicTables - Cross section HTAB data
• HdfStorageArea - Storage area volume-elevation curves
• HdfChannelCapacity - 1D channel capacity analysis
• HdfStruc1D - 1D inline structure data
• HdfPipe - Pipe network analysis
• HdfPump - Pump station analysis

Geometry Modules

Classes for parsing and authoring geometry files:

• RasGeometry - Cross sections, storage, connections
• GeomCrossSection - Cross-section builder and blocked obstructions
• GeomBridge - Bridge geometry authoring
• GeomBcLines - 2D boundary condition line authoring
• GeomLateral - Lateral structure parsing
• GeomStorage - Storage area and 2D flow area writing
• GeomLevee - Levee read/write
• RasGeometryUtils - Parsing utilities
• RasStruct - Inline structures
• RasBreach - Breach parameters

Terrain Modules

Classes for terrain creation, modification writing, and terrain-modification analysis:

• RasTerrain - Terrain HDF creation from rasters
• RasTerrainModWriter / RasTerrainModification - Line and polygon terrain modification HDF/.rasmap writing
• RasTerrainMod - Terrain profile and volume comparison with modifications applied

Fixit Module

Automated geometry repair:

• RasFixit - Fix blocked obstruction overlaps
• FixResults - Fix operation results
• log_parser - HEC-RAS log parsing for error detection

DSS Modules

Classes for reading DSS files:

• RasDss - DSS file operations

Remote Modules

Classes for distributed execution:

• LocalWorker - Local parallel execution
• PsexecWorker - Windows remote execution
• DockerWorker - Container execution
• init_ras_worker - Factory function
• compute_parallel_remote - Distributed execution

Usage Pattern

All primary classes use static methods:

Python

# No instantiation needed
from ras_commander import RasCmdr, RasPlan

# Direct static method calls
RasCmdr.compute_plan("01")
RasPlan.set_num_cores("01", 4)

Decorators

RAS Commander uses two key decorators that affect method behavior:

@standardize_input

Automatically converts various input types to the correct HDF file path. This decorator is applied to all HDF methods.

Accepted Input Types:

Input Type	Example	Behavior
Plan number (str)	"01", "p01"	Looks up HDF path in ras.plan_df
Plan number (int)	1, 2	Converted to string, then lookup
Path object	Path("x.hdf")	Used directly if file exists
String path	"/path/to.hdf"	Converted to Path, used directly
h5py.File	hdf_file	Extracts filename from object

file_type Parameter:

Python

@standardize_input(file_type='plan_hdf')  # Default - looks for .p##.hdf
@standardize_input(file_type='geom_hdf')  # Looks for .g##.hdf
@standardize_input(file_type='plan')      # Looks for .p## (plain text)

Usage Examples:

Python

from ras_commander import HdfResultsMesh, init_ras_project

init_ras_project("/path/to/project", "6.5")

# All of these are equivalent:
HdfResultsMesh.get_mesh_max_ws("01")           # Plan number string
HdfResultsMesh.get_mesh_max_ws(1)              # Integer
HdfResultsMesh.get_mesh_max_ws("p01")          # With 'p' prefix
HdfResultsMesh.get_mesh_max_ws(Path("x.hdf"))  # Path object
HdfResultsMesh.get_mesh_max_ws("/path/to.hdf") # String path

Project Initialization Required

When using plan/geometry numbers (not direct paths), you must first call init_ras_project() to populate the ras.plan_df lookup table.

@log_call

Automatic logging decorator applied to most methods. Logs function entry/exit at DEBUG level.

Python

@log_call
def my_function():
    ...

# Logs: "Calling my_function"
# Logs: "Finished my_function"

Enable debug logging to see these messages:

Python

import logging
logging.getLogger('ras_commander').setLevel(logging.DEBUG)