emerge 3.0.1

Introduction

EMerge is a python based FEM EM library for the time harmonic helmholtz formulation. It is thus best suited for Electromagnetic wave phenomenon. You can use it to simulate:

• RF Filters
• Signal propagation through PCBs
• Antennas
• Optycal systems
• Arrays and periodic structures
• Much more!

It is designed to be as easy to use and compatible as possible. It runs on all operating systems and on all hardware.

EMerge is designed to have your entire simulation start and finish in the same Python script (or more if you want). You require no awkward configuration files, JSON's, external software to do modelling etc. It allows you to do everything in Python:

• Geometry Creation/description |
• Material assignment |
• Meshing + mesh settings and adaptive mesh refinement |
• Boundary condition setup |
• Solving |
• Post processing and visualization |

If you have questions, suggestions, bug reports or just want to hang out, feel free to join the discord!

Discord Invitation

How to install

You can now install the basic version of emerge from PyPi!

pip install emerge

Direct solvers

EMerge solves all systems with direct solvers only. Some are faster than others. Depending on the operating system and hardware you have, some might work better and/or are easier to install than others. EMerge picks a solver automatically; em.solvers.available() lists the solvers installed on your system and model.set_solver(em.solvers.Sparta) selects one yourself.

SPARTA (recommended)

For the best performance, install SPARTA, the open source sparse direct solver made for EMerge. It is the fastest CPU solver for EMerge, and it can also run on the GPU: Apple silicon (Metal) and AMD (Vulkan).

Install the wheel of the latest SPARTA release, with the version of that release in the link. For example, for v0.3.2:

pip install sparta-solver --find-links https://github.com/FennisRobert/SPARTA/releases/expanded_assets/v0.3.2

Once installed, EMerge uses SPARTA on the CPU. Where PARDISO is available (x86) EMerge picks PARDISO for single sweeps; select SPARTA with model.set_solver(em.solvers.Sparta). To run SPARTA on the GPU, set:

model.set_device("GPU")     # or "HYBRID" for a combined GPU + CPU factorization

Threads

Set the number of CPU threads with:

em.set_threads(4)

This applies to EMerge's compiled kernels (assembly, interpolation, far fields) and is the default thread count of the solvers that support one (SPARTA, PARDISO). A run method can override it for the solver, for example model.mw.run_sweep(nthreads=4).

Settings that native libraries read when they load (the Accelerate, RSLab and MUMPS threads) must be set before importing EMerge. The emerge_config module, installed with EMerge, does that:

from emerge_config import config
config.set_acc_threads(4)   # Apple Accelerate
import emerge as em

Other solvers

from emerge_config import config
config.set_acc_threads(4)   # before importing emerge
import emerge as em

pip install emerge[cudss]

model.set_device("GPU")

conda install conda-forge::scikit-umfpack

Install GMSH Version 5.0.0 MacOS

pip install https://gmsh.info/python-packages-dev/gmsh/gmsh-5.0.0.dev1-py2.py3-none-macosx_12_0_arm64.whl --force-reinstall

Dependencies

EMerge ships compiled Rust kernels (the emr module, source in emr/). PyPI wheels include them; installing from source (pip install /path/to/EMerge or pip install git+https://github.com/FennisRobert/EMerge.git) compiles them automatically and requires a Rust toolchain (https://rustup.rs).

pip install emerge installs the required libraries automatically; you don't need to install them yourself. The optional extras are only installed when you ask for them.

PCB and CAD readers

You can read Gerber and ODB++ files using the optional emcad dependency which I also maintain. To get all the dependencies its easiest to do:

pip install emerge[cad]

Resources / Manual

You can find the latest versions of the manual on: https://www.emerge-software.com/resources/