Internal Modes

Internal Modes provides MATLAB tools for computing baroclinic vertical modes and SQG boundary modes for arbitrary stratification.

The package includes spectral, adaptive-grid, finite-difference, analytical, and WKB-based solvers, all organized around the vertical eigenvalue problems described in Early, Lelong, and Smith (2020).

The preferred API uses lowerCamel method names such as modesAtFrequency, modesAtWavenumber, surfaceModesAtWavenumber, and showLowestModesAtFrequency. Legacy UpperCamel names remain available for backward compatibility, but new code should use the lowerCamel forms.

If you use these classes in published work, please cite:

• J. Early, M. P. Lelong, and K. S. Smith, Fast and Accurate Computation of Vertical Modes, Journal of Advances in Modeling Earth Systems (2020), doi:10.1029/2019MS001939.

Start here

• Installation
• Tutorials
• Class documentation
• Version history

Main entry points

Class	Use it for
InternalModes	wrapper-based initialization that chooses an implementation and exposes the standard workflow
InternalModesSpectral	direct spectral solution of the depth-coordinate EVP
InternalModesWKBSpectral	WKB stretched-coordinate spectral solution
InternalModesAdaptiveSpectral	adaptive multi-region solution of the frequency-constant EVP
InternalModesConstantStratification	closed-form constant-stratification solutions
InternalModesExponentialStratification	closed-form exponential-stratification solutions