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'This example plots the graph of the polar equation r = 1 + sin(n * Θ). This
'figure is sometimes known as a cardioid, owing to its resemblance to a
'heart when n equals 1.
 
CLS
CONST PI = 3.141593
SCREEN 1 : COLOR 1,1             'Medium resolution, blue background.
WINDOW (-3,-2)-(3,2)             'Convert screen to Cartesian coordinates.
INPUT "Number of petals = ", N
CLS
PSET (1,0)                       'Set initial point.
FOR Angle = 0 TO 2*PI STEP .02
   R = 1 + SIN(N*Angle)          'Polar equation for "flower."
   X = R * COS(Angle)            'Convert polar coordinates to
   Y = R * SIN(Angle)            'Cartesian coordinates.
   LINE -(X,Y)                   'Draw line from previous point to new point.
NEXT
END