Grid

A Grid is a WAVI.jl object that stores information relating to the numerical grid. The key parameters, which are passed via keyword arguments in the OutputParams constructor, are as follows:

• nx: number of x grid points
• ny: number of y grid points
• nσ: number of levels in the vertical
• dx: grid spacing in x
• dy: grid spacing in y
• x0: grid origin x co-ordinate
• y0: grid origin y co-ordinate
• h_mask: Array of size nx x ny that defines domain points: ones in the h_mask indicate loations within ice domain, while zeros in the h_mask indicate locations outside of the ice domain. Defaults to trues(nx,ny), corresponding to every grid point being in the ice domain.
• u_iszero: Array of size nx x ny that defines locations of zero velocity in the x-direction: ones in the u_iszero correspond to points where the velocity in the x-direction is forced to be zero, while zeros in the u_iszero array corresponds to points where the velocity is free. Defaults to falses(nx,ny), corresponding to no restrictions on u velocity anywhere. u_iszero can also be specified by an array with entries from "North", "South", "East", and "West", which set the corresponding edges of the domain to have zero velocity boundary conditions there.
• v_iszero: As in u_iszero for the velocity in the y-direction.
• σ: Dimensionless locations of sigma (vertical) levels. Values must be increasing between 0 and 1.
• quadrature_weights: weights associated with sigma (vertical) levels used in quadrature scheme to determine depth averaged quantities (e.g. viscosity).

WAVI.jl has several grids, on which different quantities are defined (see numerical grid). A Grid object contains explicit definitions of these grids; for example, the x-coordinates of the "h grid" are stored in grid.xxh (where grid is the name of the Grid instance).

Grid(; 
nx = 80,
ny = 10,
dx = 8000.0,
dy = 8000.0,
nσ = 4,
x0 = 0.0,
y0 = -40000.0,
h_mask = nothing,
u_iszero = nothing,
v_iszero = nothing)

- 'nx': number of x grid points
- 'ny': number of y grid points
- 'dx': grid spacing in x 
- 'dy': grid spacing in y 
- 'nσ': number of levels in the vertical
- 'x0': grid origin x co-ordinate 
- 'y0': grid origin y co-ordinate
- 'h_mask': Mask defining domain points within grid
- 'u_iszero': Locations of zero u velocity points
- 'v_iszero': Locations of zero v velocity points
- 'quadrature_weights': weights associated with sigma levels used in quadrature scheme