How to Run ECHO3D on macOS

When you download the ECHO3D code on a macOS computer, the files may have an extended attribute called com.apple.quarantine. You must remove this attribute before launching the applications.

Removing the Extended Attribute:

1. Open Terminal.
2. Navigate to the Codes/MacOS_ARM directory.
3. Run the following command: xattr -c ./*

Step-by-Step Instructions for Running ECHO3D:

1. Open Terminal.
2. Navigate to the Example Directory: cd (your path)/ECHO3D_v1_4/Examples/N1_RoundStepOut_LongWake
3. Copy All Codes from the “Codes” Directory: cp ../../Codes/MacOS_ARM/* ./
4. Run Mesher: ./Mesher
5. Run InitField: ./InitField
6. Run ECHO3D: ./ECHO3D
7. Run IndirectIntegration: ./IndirectIntegration

Using Command Files for Simplified Execution:

1. Navigate to the Example Directory: cd (your path)/ECHO3D_v1_4/Examples/N1_RoundStepOut_LongWake
2. Change the File Attributes to Executable: chmod +x run_Mac.command
3. Execute the Command File:

• Double-click run_Mac.command in Finder.
• Alternatively, run it from Terminal: ./run_Mac.command

Note: These instructions are also applicable to ECHO2D.

Parallelization Options for ECHO3D and ECHO2D:

ECHO3D Parallelization:

• Technology: Uses OpenMP (or threads).
• Setup: Can only run on one computer with multiple cores.
• Configuration: Set the ThreadsNumber parameter in input.txt to a value equal to or less than the number of available cores.

ECHO2D Parallelization Options:

1. MPI Parallelization:

• Location: Codes/MacOS_ARM_MPI
• Usage: Run using the mpirun command, suitable for clusters with multiple nodes.

2. Thread-Based Parallelization:

• Location: Codes/MacOS_ARM_OpenMP
• Usage: Runs on a single computer with multiple cores.
• Configuration: The number of threads will be equal to the number of modes defined in input_in.txt using the Modes parameter.

In the example “N10_TESLACavityLong,” the azimuthal modes for calculations are specified in the input_in.txt file via the parameter “Modes.”

Modes=0 means that only the monopole mode (m=0) will be calculated. Modes=0 1 means that both monopole and dipole modes will be calculated.

The calculation of each mode itself is not parallelized; however, different modes can be calculated in parallel. This means that:

In the first case (Modes=0), you should use “mpirun -np 1” or simply run the code without the mpirun command. In the second case (Modes=0 1), you can use a maximum of two processors with the command “mpirun -np 2.”

For rectangular geometries, where typically 30-100 modes are needed, parallelization can be beneficial.

For rotationally symmetric modes, the ECHOz2 code can be used. This code calculates only one mode at a time, but the computation is parallelized with threads/OpenMP, allowing multiple processors to work in parallel for a single mode calculation. ECHOz2 includes a GUI; however, there is currently no macOS version available. If you have Parallels and install Windows ARM, the ARM version of ECHOz2 runs efficiently on a Mac.