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makeDisc

Create a binary map of a filled disc within a 2D grid

Syntax

disc = makeDisc(Nx, Nz, cx, cz, radius)
disc = makeDisc(Nx, Nz, cx, cz, radius, plot_disc)

Description

makeDisc creates a binary map of a filled disc within a two-dimensional grid (the disc position is denoted by 1's in the matrix with 0's elsewhere). A single pixel is taken as the disc centre thus the total diameter of the disc will always be an odd number of pixels. As the returned disc has a constant pixel radius, if used within a k-space grid where dx and dz are not equal, the disc will appear oval shaped. If part of the disc overlaps the grid edge, the rest of the disc will wrap to the grid edge on the opposite side. The plot that is displayed after calling makeDisc(128, 128, 64, 64, 30, true) is given below.

Inputs

Nx, Ny

size of the 2D grid [number of pixels]

cx, cy

centre of the disc [pixel coordinates]

radius

disc radius [number of pixels]

Optional Inputs

plot_circle

Boolean controlling whether the disc is plotted using imagesc (default = false)

Outputs

disc

2D binary map of a filled disc

Examples

See Also

makeCircle, makeBall


© 2009, 2010 Bradley Treeby and Ben Cox.