Wondering about learning Python

[Lee Harr]

On 2004-07-22, Chris <nospam@[> wrote:
> I've written a small QBASIC program which draws a spiral. Here is the 
> code:
>
> SCREEN 12
> CLS
> FOR t = 1 TO 400 STEP .01
> x = .5 * t * COS(t)
> y = .5 * t * SIN(t)
> PSET (x + 320, y + 240)
> NEXT t
>
> I noticed that it generated some interesting patterns, probably as a 
> result of rounding errors.  These can be explored further by making the 
> spiral tighter.
>
> Anyway, I wonder if anyone would be so kind as to convert it to Python.
>


It is not a direct translation, but here is how I made a spiral
method for my Penguin object in pygsear
(http://www.nongnu.org/pygsear/)


class Penguin(Turtle):
    def spiral(self, turns=1, rPerT=100, stepsPerT=60, connect=0):
        '''Make a spiral shape

        @param turns: number of times to go around the spiral.
        @param rPerT: amount spiral grows per turn.
        @param stepsPerT: number of line segments in each spiral turn.
            (more segments makes a smoother curve)
        @param connect: if True, draw a line from the center to each
            generated point on the curve.

        '''

        center = self.get_position()
        for c in range(turns * stepsPerT):
            f = (PIx2 * rPerT/stepsPerT) * (float(c) / stepsPerT)
            self.forward(f)
            self.right(360.0 / stepsPerT)
            if connect:
                p = self.get_position()
                self.lineTo(center)
                self.lineTo(p)