Wavenumbers, modes, and indices

Working with the WaveVortexModel requires working with wavenumbers (such as \(k\) and \(l\)), modes (such as geostrophic modes, or mode number \(j\)), and indices into matrices. There are many best practices and tools for working with wavenumbers, mode, and indices.

Definitions

A wavenumber is a spatial frequency with units of radians per meter. All WVTransform classes have horizontal wavenumbers \(k\) and \(l\), and the constant stratification class also has a vertical wavenumber \(m\).

A mode is a unitless integer quantity. The model refers to kMode and lMode, and j all as unitless modes. Additionally, a geostrophic solution is also a mode (as are the other linear solutions).

An index is a location in memory of a particular variable. Matlab uses subscript indices, linear indices, and logical indexing for different ways of accessing memory. The prefered method of indexing is local indexing.