Import Hydrodynamic Coefficients

Import Hydrodynamic Coefficients.

This example demonstrates how to import hydrodynamic coefficients data into SIMA using the SIMAPy API.

The script shows how to use SIMA along with simapy to import hydrodynamic coefficients from datasets generated by WAMIT. The same approach can be used to import data from HydroD/WADAM or any other file format which is supported by SIMA.

Features:
Hydrodynamic Data Import:

Demonstrates importing hydrodynamic coefficients from WAMIT

SIMA Integration:

Shows the workflow for bringing external hydrodynamic data into SIMA

Data Export:

Saves the processed data to a JSON file that can be imported into SIMA

Requirements:

  • Environment variable SRE_EXE which points to the sre executable of SIMA

  • SIMA version 4.4.0 or later

Example

Basic usage of this script:

>>> python import_hydrodynamic_coefficients.py

This example is particularly useful for importing hydrodynamic data from external analysis tools and preparing models that require accurate hydrodynamic coefficients for simulations.

import_file(workspace, filename)[source]

Import a file of a type supported by SIMA as a list of tasks.

This function uses the SIMA Runtime Engine (SRE) to import data from external files into SIMA’s internal format. It supports various file formats including WAMIT output files and HydroD/WADAM G1.SIF files.

Parameters:

  • workspace (Path) – Directory where SRE will store temporary files

  • filename (Path) – Path to the file to import

Returns:

A list of imported SIMA tasks

Return type:

list

Notes

The function uses an environmental variable SRE_EXE to locate the SIMA installation, make sure it is set before running.

main()[source]

Import hydrodynamic coefficients from WAMIT dataset using SRE and export to JSON file.

This function demonstrates the complete workflow for importing hydrodynamic data from WAMIT: 1. Create a workspace for the import/export operation 2. Import the WAMIT .out file using the import_file helper function 3. Export the imported task to a JSON file for later use in SIMA

The generated JSON file can be imported into SIMA to set up simulations using the hydrodynamic coefficients.

Returns:

The function writes output to disk but doesn’t return any value

Return type:

None

run_sima(workspace, commands)[source]

Run SIMA with the given workspace directory and command line arguments.

The function uses an environmental variable SRE_EXE to locate the SIMA installation, make sure it is set before running.

Source Code

import_hydrodynamic_coefficients.py
  1"""Import Hydrodynamic Coefficients.
  2
  3This example demonstrates how to import hydrodynamic coefficients data into SIMA using the SIMAPy API.
  4
  5The script shows how to use SIMA along with simapy to import hydrodynamic
  6coefficients from datasets generated by WAMIT. The same approach can be used to import
  7data from HydroD/WADAM or any other file format which is supported by SIMA.
  8
  9Features:
 10    Hydrodynamic Data Import:
 11        Demonstrates importing hydrodynamic coefficients from WAMIT
 12    SIMA Integration:
 13        Shows the workflow for bringing external hydrodynamic data into SIMA
 14    Data Export:
 15        Saves the processed data to a JSON file that can be imported into SIMA
 16
 17Requirements:
 18    - Environment variable `SRE_EXE` which points to the sre executable of SIMA
 19    - SIMA version 4.4.0 or later
 20
 21Example:
 22    Basic usage of this script:
 23    
 24    >>> python import_hydrodynamic_coefficients.py
 25    
 26    This example is particularly useful for importing hydrodynamic data from external 
 27    analysis tools and preparing models that require accurate hydrodynamic coefficients
 28    for simulations.
 29"""
 30import os
 31import shutil
 32from pathlib import Path
 33
 34from simapy.sre import SIMA
 35from simapy.sima_reader import SIMAReader
 36from simapy.sima_writer import SIMAWriter
 37
 38from simapy.sima.command import ImportCommand, ExportCommand
 39
 40SCRIPT_DIR = Path(os.path.realpath(os.path.dirname(__file__)))
 41
 42
 43def main():
 44    """
 45    Import hydrodynamic coefficients from WAMIT dataset using SRE and export to JSON file.
 46    
 47    This function demonstrates the complete workflow for importing hydrodynamic data from WAMIT:
 48    1. Create a workspace for the import/export operation
 49    2. Import the WAMIT .out file using the import_file helper function
 50    3. Export the imported task to a JSON file for later use in SIMA
 51    
 52    The generated JSON file can be imported into SIMA to set up simulations using the
 53    hydrodynamic coefficients.
 54    
 55    Returns:
 56        None: The function writes output to disk but doesn't return any value
 57    """
 58    # Here we use the import_file function defined below to import data from the WAMIT
 59    # dataset by pointing at the .out-file. The same function could be used to for
 60    # example to import a G1.SIF file created by HydroD/WADAM as well.
 61    # The function returns a list of tasks because certain file formats (e.g. stasks)
 62    # might contain multiple tasks. WAMIT result files only create a single task
 63    # hence the variable is assigned to the zeroth element of the list.
 64
 65    workspace = Path("output/simo/simo_wamit_import")
 66    if workspace.exists():
 67        shutil.rmtree(workspace, ignore_errors=True)
 68    os.makedirs(workspace)
 69
 70    task = import_file(workspace, SCRIPT_DIR / "wamit_data" / "sima.out")[0]
 71
 72    # After the task has been imported we could do some manipulations to it, add more
 73    # data and perhaps make SIMA run a simulation with the task. For this example we
 74    # just export it to a JSON file called imported.json. This file can be imported
 75    # into SIMA in order to inspect the results.
 76    file = workspace / "simo_wamit_import.json"
 77    os.makedirs(file.parent, exist_ok=True)
 78    SIMAWriter().write([task], file)
 79
 80
 81def import_file(workspace: Path, filename: Path):
 82    """Import a file of a type supported by SIMA as a list of tasks.
 83
 84    This function uses the SIMA Runtime Engine (SRE) to import data from external
 85    files into SIMA's internal format. It supports various file formats including WAMIT
 86    output files and HydroD/WADAM G1.SIF files.
 87    
 88    Args:
 89        workspace (Path): Directory where SRE will store temporary files
 90        filename (Path): Path to the file to import
 91        
 92    Returns:
 93        list: A list of imported SIMA tasks
 94        
 95    Notes:
 96        The function uses an environmental variable SRE_EXE to locate the SIMA installation,
 97        make sure it is set before running.
 98    """
 99    out_file = workspace / "out.json"
100
101    # Run SIMA to import SIF file and export JSON
102    import_command = ImportCommand(file=str(filename.absolute()))
103    export_command = ExportCommand(file=str(out_file.absolute()), delete=True)
104    commands = [import_command, export_command]
105
106    run_sima(workspace, commands)
107
108    # Import JSON file exported by SIMA
109    return SIMAReader().read(out_file)
110
111
112def run_sima(workspace: Path, commands: list):
113    """Run SIMA with the given workspace directory and command line arguments.
114
115    The function uses an environmental variable SRE_EXE to locate the SIMA installation,
116    make sure it is set before running.
117    """
118    sima = SIMA()
119    sima.run(workspace, commands)
120
121
122if __name__ == "__main__":
123    main()