This code implements the Fast Marching Method (FMM; Sethian et al., 1996) for solving the eikonal equation in Cartesian or spherical coordinates in 2 or 3 dimensions. The method implements mixed first- and second-order finite differences.

PyKonal offers two features that are absent from the comparable scikit-fmm package: (a) an implementation in spherical coordinates, and (b) functionality to compute shortest-traveltime paths.

Documentation is available here.

If you make use of this code in published work, please cite White et al. (2020).

Download the latest release.

sh$> conda create --name pykonal -c conda-forge python=3.8 'cython>=0.29.14' h5py numpy scipy
sh$> conda activate pykonal
(pykonal)sh$> cd path/to/pykonal
(pykonal)sh$> pip install .

sh$> pip install cython>=0.29.14 h5py numpy scipy
sh$> cd path/to/pykonal
sh$> pip install .

Please report bugs, feature requests, and questions through the Issues tracker.

1. Sethian, J. A. (1996). A fast marching level set method for monotonically advancing fronts. Proceedings of the National Academy of Sciences, 93(4), 1591–1595. https://doi.org/10.1073/pnas.93.4.1591
2. White, M. C. A., Fang, H., Nakata, N., & Ben-Zion, Y. (2020). PyKonal: A Python Package for Solving the Eikonal Equation in Spherical and Cartesian Coordinates Using the Fast Marching Method. Seismological Research Letters, 91(4), 2378-2389. https://doi.org/10.1785/0220190318