In Python 2.6.4, why do I get a syntax error for a function call, of which the function is defined and works perfectly on its own?

This happens in IDLE and Windows 7 RC1 (if that helps). Here is the module:

    from math import *
from TurtleWorld import *

world = TurtleWorld()
bob = Turtle()
bob.delay = 0.1

def polyline(turtle, length, n, angle):
    for i in range(n):
        fd(turtle, length)
        rt(turtle, angle)

def polygon(turtle, lengt开发者_如何学Goh, n):
    """ polygon uses a turtle to draw a polygon
        with n sides of the given length.
    """
    angle = 360.0/n
    polyline(turtle, length, n, angle)

def spokes(turtle, length_of_spoke, number_of_spokes):
    angle = 360.0/number_of_spokes
    for i in range(number_of_spokes):
       turtle.fd(length_of_spoke)
       turtle.pd
       turtle.bk(length_of_spoke)
       turtle.rt(angle)
       turtle.pu

def pie(turtle, length_of_side, number_of_sides):
    """pie uses a turtle to draw a polygon
        with sides of the given length and with the given
        number of sides.
    """
    angle = 360.0/number_of_sides
    length_of_spoke = length_of_side/(2*sin(pi/180*angle/2)
    spokes(turtle, length_of_spoke, number_of_sides)
    turtle.pd
    turtle.fd(length_of_spoke)
    turtle.lt(270-angle/2)
    polygon(turtle, length_of_side, number_of_sides)

spokes(bob, 30, 11)

wait_for_user()

When I run the program, I get the error: There is an error in your program: invalid syntax. IDLE then highlights the "spokes" word within the pie-function.

If I comment-out the whole pie-function, the program runs perfectly.

At quick glance are you missing a closing parenthesis at the end of the line before you call spokes()?

length_of_spoke = length_of_side/(2*sin(pi/180*angle/2))

instead of

length_of_spoke = length_of_side/(2*sin(pi/180*angle/2)

The previous line is missing a closing parenthesis. It should read like this instead:

length_of_spoke = length_of_side/(2*sin(pi/180*angle/2))

There is a closing parenthesis missing in the previous line:

length_of_spoke = length_of_side/(2*sin(pi/180*angle/2)

Others have already pointed out the actual syntax error, so I won't say any more about that. One thing I will add though is that if I get a syntax error, the first place I look is on the lines before the function. Usually it's something like a paren missing or a comma in the wrong place.