ptypy.core.xy.spiral_scan#

ptypy.core.xy.spiral_scan(dr=1.5e-06, r=7.5e-06, maxpts=None)#

Generates a spiral scan.

Parameters:

r (float) – Number of radial steps from center, nr + 1 shells will be made
dr (float) – Step size (shell spacing)
nth (int, optional) – Number of points in first shell

Returns:

pos – A (N,2)-array of positions. It is

Return type:

ndarray

Examples

>>> from ptypy.core import xy
>>> from matplotlib import pyplot as plt
>>> pos = xy.spiral_scan()
>>> plt.plot(pos[:, 1], pos[:, 0], 'o-'); plt.show()