我实现了一个函数,它给出了离散值的包络曲线。我想可能有一个错误,因为当我在帖子底部提供给你的日期测试时,我得到的信封曲线的真实数据点与图中所示的不同
from scipy.interpolate import interp1d
import numpy as np
import matplotlib.pyplot as plt
def enveloppe(s):
u_x = [0,]
u_y = [s[0],]
q_u = np.zeros(s.shape)
for k in xrange(1,len(s)-1):
if (np.sign(s[k]-s[k-1])==1) and (np.sign(s[k]-s[k+1])==1):
u_x.append(k)
u_y.append(s[k])
u_x.append(len(s)-1)
u_y.append(s[-1])
u_p = interp1d(u_x,u_y, kind = 'cubic',bounds_error = False, fill_value=0.0)
#Evaluate each model over the domain of (s)
for k in xrange(0,len(s)):
q_u[k] = u_p(k)
return q_u
fig, ax = plt.subplots()
ax.plot(S, '-o', label = 'magnitude')
ax.plot(envelope(S), '-o', label = 'enveloppe magnitude')
ax.legend()
Data S : array([ 9.12348621e-11, 6.69568658e-10, 6.55973768e-09,
1.26822485e-06, 4.50553316e-09, 5.06526113e-07,
2.96728433e-09, 2.36088205e-07, 1.90802318e-09,
1.15867354e-07, 1.18504790e-09, 5.72888034e-08,
6.98672478e-10, 2.75361324e-08, 3.82391643e-10,
1.25393143e-08, 1.96697343e-10, 5.96979943e-09,
1.27009013e-10, 4.46365555e-09, 1.31769958e-10,
4.42024233e-09, 1.42514400e-10, 4.17757107e-09,
1.41640360e-10, 3.65170558e-09, 1.29784598e-10,
2.99790514e-09, 1.11732461e-10])