InternalModesBase

Define the shared contract for all internal-mode solvers.

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Declaration

classdef (Abstract) InternalModesBase < handle

Overview

InternalModesBase is the abstract base class for the concrete solver implementations. It stores the common physical parameters, normalization choices, and boundary-condition state, and it defines the shared public interface for requesting modes at fixed wavenumber or fixed frequency.

Following Section 2.3 of Early, Lelong, and Smith (2020), the package centers on the vertical structure functions \(F_j(z)\) and \(G_j(z)\) with equivalent depths \(h_j\), connected by

\[(N^2 - \omega^2) G_j = -g \, \partial_z F_j, \qquad F_j = h_j \, \partial_z G_j.\]

Concrete subclasses solve either the fixed-\(K\) or fixed-\(\omega\) eigenvalue problems using spectral, finite-difference, analytical, or WKB-based formulations, but they all expose the same shared state documented here.

Topics

• Inspect grids and stratification
  • Lz Total water-column depth \(D = zMax - zMin\).
  • N2 Buoyancy frequency squared sampled on zOut.
  • f0 Coriolis parameter at the selected latitude.
  • latitude in degrees used to compute f0.
  • rho Background density sampled on zOut.
  • rho0 Reference surface density.
  • rho_z First depth derivative of the background density sampled on zOut.
  • rho_zz Second depth derivative of the background density sampled on zOut.
  • rotationRate Planetary rotation rate in radians per second.
  • z Output depth grid on which public profiles and modes are returned.
  • zDomain Two-element depth domain [zMin zMax].
  • zMax Maximum depth in zDomain.
  • zMin Minimum depth in zDomain.
• Configure normalization and boundaries
  • lowerBoundary Lower boundary condition at the ocean bottom.
  • normalization Mode normalization convention.
  • upperBoundary Upper boundary condition at the ocean surface.
• Compute modes
  • modesAtFrequency Return vertical modes for a fixed frequency.
  • modesAtWavenumber Return vertical modes for a fixed horizontal wavenumber.
  • nModes Optional cap on the number of modes returned.

Developer Topics

These items document internal implementation details and are not part of the primary public API.

• Developer topics
  • gridFrequency Last fixed frequency used to build an adaptive grid, when applicable.
  • requiresMonotonicDensity Flag indicating whether the concrete solver requires monotonic density.
  • shouldShowDiagnostics Toggle diagnostic messages from the active solver.

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