makeCircle

Create a binary map of a circle within a 2D grid.

Syntax

circle = makeCircle(Nx, Ny, cx, cy, radius)
circle = makeCircle(Nx, Ny, cx, cy, radius, arc_angle)
circle = makeCircle(Nx, Ny, cx, cy, radius, arc_angle, plot_circle)

Description

makeCircle creates a binary map of a circle or arc (using the midpoint circle algorithm) within a two-dimensional grid (the circle position is denoted by 1's in the matrix with 0's elsewhere). A single grid point is taken as the circle centre thus the total diameter will always be an odd number of grid points. The plot that is displayed after calling makeCircle(128, 128, 64, 64, 30, (215/180)*pi, true); is given below.

Inputs

Nx, Ny	size of the 2D grid [grid points]
cx, cy	centre of the circle [grid points], if set to 0, the centre of the grid is used
radius	circle radius [grid points]

Optional Inputs

arc_angle	arc angle for incomplete circle [radians] (default = 2*pi)
plot_circle	Boolean controlling whether the circle is plotted using imagesc (default = false)

Outputs

circle

2D binary map of a circle

Examples

• Using A Binary Sensor Mask
• Simulating Transducer Field Patterns
• Focussed Detector in 2D
• Focussed 2D Array with Directional Elements
• 2D Time Reversal For A Circular Sensor
• Image Reconstruction With Bandlimited Sensors
• Image Reconstruction With Compensation For Acoustic Absorption

See Also

makeCartCircle, makeDisc