Home :: Examples :: Astroid


Astroid is a particular type of curve: a hypocycloid with four cusps.

A circle of radius 1/4 rolls around inside a circle of radius 1 and a point on its circumference traces an astroid. A line segment of length 1 slides with one end on the x-axis and the other on the y-axis, so that it is tangent to the astroid. The parametric equations are:

x = (cos(p))^3
y = (sin(p))^3

To plot function Astroid use the folowing script:

# Example
# 2D. Astroid

# z must be zero
z = 0

# t-parameter
tmin = 0
tmax = 2*pi

# Constant
a = 8

# Calculations
x = a * cos(t)^3
y = a * sin(t)^3