我的闲散代码(应该)解决两个物体的运动方程,但结果是粒子运行方式,我无法找到错误在哪里
import numpy as np
import matplotlib.pyplot as plt
plt.style.use('ggplot')
DIM = 2
N = 2
ITER = 1000
def acc(r, v, a):
for i in range(N - 1):
for j in range(i+1, N):
r2 = 0.0
rij = [0.0, 0.0]
for k in range(DIM):
rij[k] = r[i][k] - r[j][k]
r2 += rij[k] * rij[k]
fg = -1.0 /np.power(np.sqrt(r2), 3)
for k in range(DIM):
a[i][k] += fg * rij[k]
a[j][k] -= fg * rij[k]
return a
def verlet(r, v, a, dt):
for i in range(N):
for k in range(DIM):
v[i][k] += 0.5 * a[i][k] * dt
r[i][k] += v[i][k] * dt
a = acc(r, v, a)
for i in range(N):
for k in range(DIM):
v[i][k] += 0.5 * a[i][k] * dt
return [r,v]
r = np.zeros((N, DIM))
v = np.zeros((N ,DIM))
a = np.zeros((N, DIM))
r[0] = [0.5,0.0]
v[0] = [0.0,1.0]
r[1] = [-0.5,0.0]
v[1] = [0.0,-1.0]
dt = 0.01
plt.ion()
for i in range(ITER):
r,v = verlet(r, v, a, dt)
plt.scatter(r[0][0], r[0][1])
plt.scatter(r[1][0], r[1][1],color='yellow')
plt.pause(0.00005)