Draw a Parametric Curve

Demonstrates how to draw a parametric curve Python.

import rhinoscriptsyntax as rs
import math

# that we are passing a function as a parameter
def DrawParametricCurve(parametric_equation):
"Create a interpolated curve based on a parametric equation."
# Get the minimum parameter
t0 = rs.GetReal("Minimum t value", 0.0)
if( t0==None ): return

# Get the maximum parameter
t1 = rs.GetReal("Maximum t value", 1.0)
if( t1==None ): return

# Get the number of sampling points to interpolate through
count = rs.GetInteger("Number of points", 50, 2)
if count<1: return

arrPoints = list()
#Get the first point
point = parametric_equation(t0)
arrPoints.append(point)

#Get the rest of the points
for x in xrange(1,count-2):
t = (1.0-(x/count))*t0 + (x/count)*t1
point = parametric_equation(t)
arrPoints.append(point)

#Get the last point
point = parametric_equation(t1)
arrPoints.append(point)

#Customizable function that solves a parametric equation
def __CalculatePoint(t):
x = (4*(1-t)+1*t ) * math.sin(3*6.2832*t)
y = (4*(1-t)+1*t ) * math.cos(3*6.2832*t)
z = 5*t
return x,y,z

##########################################################################
# Check to see if this file is being executed as the "main" python
# script instead of being used as a module by some other python script
# This allows us to use the module which ever way we want.
if( __name__ == "__main__" ):
#Call the function passing another function as a parameter
DrawParametricCurve(__CalculatePoint)