为什么交叉光谱在mlab和scipy.signal中有所不同？

Question

我有两个信号

T fnktptr; //Error: field ‘Event<int()>::fnktptr’ invalidly declared function type

我想获得连贯性

import numpy as np
import matplotlib.pyplot as plt
from matplotlib import mlab
import mpld3
from scipy import signal

mpld3.enable_notebook()

nfft = 256
dt = 0.01
t = np.arange(0, 30, dt)
nse1 = np.random.randn(len(t))  * 0.1              # white noise 1
nse2 = np.random.randn(len(t))  * 0.1              # white noise 2



# two signals with a coherent part and a random part
s1 = np.sin(2*np.pi*1*t) + nse1
s2 = np.sin(2*np.pi*1*t+np.pi) + nse2 

plt.plot(s1, 'r', s2, 'g')
plt.show()

和相移

cxy, fcoh = plt.cohere(s1, s2, nfft, 1./dt)
fcoh,cxy = signal.coherence(s1,s2, nfft=nfft, fs=1./dt)
plt.hold(True)
plt.plot(fcoh, cxy)
#plt.xlim(0, 5)
plt.show()

我尝试使用(csd, f) = mlab.csd(s1, s2, NFFT=nfft, Fs=1./dt) fig = plt.figure() angle = np.angle(csd,deg =False) angle[angle<-np.pi/2] += 2*np.pi plt.plot(f, angle, 'g') plt.hold(True) (f, csd) = signal.csd(s1, s2, fs=1./dt, nfft=nfft) angle = np.angle(csd,deg =False) angle[angle<-np.pi/2] += 2*np.pi plt.plot(f, angle,'r') #plt.xlim(0,5) plt.show() 和scipy。谁能解释为什么我会得到不同的结果？