import math

coords = [(math.sin(x*math.pi/500), math.cos(x*math.pi/500)) for x in range(10000000)]

@profile
def f():
    thetas = [math.atan2(coords[0][1], coords[0][0])]
    prev = thetas[0]
    for index in range(1, len(coords)):
        coord = coords[index]
        theta = math.atan2(coord[1], coord[0]) + (prev // (2*math.pi)) * (2 * math.pi)
        while theta - prev > math.pi:
            theta -= 2*math.pi
        while prev - theta > math.pi:
            theta += 2*math.pi
        assert abs(theta - prev) < math.pi/2
        thetas.append(theta)
        prev = theta

f()

##Timer unit: 4.10528e-07 s
##
##File: <nope>
##Function: f at line 5
##Total time: 114.679 s
##
##Line #      Hits         Time  Per Hit   % Time  Line Contents
##==============================================================
##     5                                           @profile
##     6                                           def f():
##     7         1           37     37.0      0.0      thetas = [math.atan2(coords[0][1], coords[0][0])]
##     8         1            3      3.0      0.0      prev = thetas[0]
##     9  10000000     19992061      2.0      7.2      for index in range(1, len(coords)):
##    10   9999999     24776580      2.5      8.9          coord = coords[index]
##    11   9999999     61555671      6.2     22.0          theta = math.atan2(coord[1], coord[0]) + (prev // (2*math.pi)) * (2 * math.pi)
##    12   9999999     32881846      3.3     11.8          while theta - prev > math.pi:
##    13                                                       theta -= 2*math.pi
##    14  14990820     40634922      2.7     14.5          while prev - theta > math.pi:
##    15   4990821     15307461      3.1      5.5              theta += 2*math.pi
##    16   9999999     36460032      3.6     13.1          assert abs(theta - prev) < math.pi/2
##    17   9999999     27592582      2.8      9.9          thetas.append(theta)
##    18   9999999     20143660      2.0      7.2          prev = theta