k-Wave Toolbox

makeGrid

Create k-Wave grid structure

Syntax

kgrid = makeGrid(Nx, dx)
kgrid = makeGrid(Nx, dx, Ny, dy)
kgrid = makeGrid(Nx, dx, Ny, dy, Nz, dz)

Description

makeGrid creates an object of the kWaveGrid class containing the grid coordinates and wavenumber matrices used in k-Wave simulations. The grid structures are indexed as: (x, 1) in 1D; (x, y) in 2D; (x, y, z) in 3D.

Note For older versions of MATLAB in which custom class definitions are not supported, makeGrid returns a MATLAB grid structure with the same fields. This structure requires additional memory compared to an object of the kWaveGrid class.

Inputs

`Nx, Ny, Nz`	number of grid points in each Cartesian direction
`dx, dy, dz`	grid point spacing in each Cartesian direction [m]

Outputs

kgrid

k-Wave grid structure used by the simulation and reconstructions functions within k-Wave

The structure kgrid has the following fields:

Fieldname	Description
`kgrid.k`	ND grid of the scalar wavenumber
`kgrid.k_max`	maximum spatial frequency supported by the grid
`kgrid.t_array`	evenly spaced array of time values [s] (set to 'auto' by `makeGrid`)
`kgrid.Nt`	number of time steps (set to 'auto' by `makeGrid`)
`kgrid.dt`	time step [s] (set to 'auto' by `makeGrid`)
`kgrid.dim`	number of spatial dimensions
`kgrid.total_grid_points`	total number of grid points

And for each spatial dimension x, y, z:

Fieldname	Description
`kgrid.Nx`	number of grid points
`kgrid.dx`	grid point spacing [m]
`kgrid.x`	plaid ND grid of the x coordinate centered about 0 [m]
`kgrid.x_vec`	1D vector of the x coordinate [m]
`kgrid.x_size`	length of grid dimension [m]
`kgrid.kx`	plaid ND grid of the wavenumber components centered about 0
`kgrid.kx_vec`	1D vector of the wavenumber components
`kgrid.kx_max`	maximum spatial frequency supported by the grid in the x direction

For example, running kgrid = makeGrid(128, 0.1, 128, 0.1) at the command line will return:

kgrid = makeGrid(128, 0.1, 128, 0.1)

kgrid = 

  kWaveGrid

  Properties:
                   Nx: 128
                   Ny: 128
                   Nz: 0
                   dx: 0.1000
                   dy: 0.1000
                   dz: 0
               kx_vec: [128x1 double]
               ky_vec: [128x1 double]
               kz_vec: 0
                    k: [128x128 double]
               kx_max: 31.4159
               ky_max: 31.4159
               kz_max: 0
                k_max: 31.4159
              t_array: 'auto'
                  dim: 2
                    x: [128x128 double]
                    y: [128x128 double]
                    z: 0
                   kx: [128x128 double]
                   ky: [128x128 double]
                   kz: 0
                x_vec: [128x1 double]
                y_vec: [128x1 double]
                z_vec: 0
               x_size: 12.8000
               z_size: 0
               y_size: 12.8000
                   dt: 'auto'
                   Nt: 'auto'
    total_grid_points: 16384

makeGrid

Syntax

Description

Inputs

Outputs

See Also