from cresset import flare

用鼠标单击蛋白A链PHE82侧链苯环的六个碳原子，使之处于被选中状态：

atoms = flare.main_window().picked_atoms

for a in atoms:
    print(a.pos)

(-1.7269999980926514, 67.61199951171875, 86.1969985961914)
(-1.371000051498413, 68.43499755859375, 85.13099670410156)
(-1.8480000495910645, 68.12799835205078, 83.86199951171875)
(-2.6730000972747803, 67.01300048828125, 83.65299987792969)
(-3.0260000228881836, 66.19499969482422, 84.7229995727539)
(-2.552000045776367, 66.49400329589844, 86.0009994506836)

求PHE820侧链苯环的几何中心cent1

import numpy as np
cent1 = np.array([0,0,0])
for i in range(0,len(atoms)):
    cent1 = cent1 + np.array(atoms[i].pos)

cent1 = cent1/len(atoms)

print(cent1)

[-2.19950004 67.31283315 84.92783229]

用鼠标单击选择配体杂环的六个原子：

atoms = flare.main_window().picked_atoms

求配体六员杂环的几何中心点cent2：

cent2 = np.array([0,0,0])
for i in range(0,len(atoms)):
    cent2 = cent2 + np.array(atoms[i].pos)
cent2 = cent2/len(atoms)

print(cent2)

[ 0.41699999 64.70199903 84.9350001 ]

计算两个苯环中心center1与center2之间的距离d

d = np.linalg.norm(cent1 - cent2)

print(d)

3.696292550843733