Generate a spiral pattern, moving outwards from the centre position (0,0). Python code.

spiral_pattern.py

# Generate a spiral pattern, moving outwards from the centre position (0,0)
# The size parameter sets the size of the spiral "shell"
SIZE = 5

x, y = 0, 0
dx, dy = 0, -1

for i in range(SIZE**2):
    if (x == y) or (x < 0 and x == -y) or (x > 0 and x == 1-y):
        dx, dy = -dy, dx

    print "Position:", (x, y)
    x, y = x+dx, y+dy