matplotlib.pyplot.phase_spectrum() in Python

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Matplotlib is a library in Python and it is numerical – mathematical extension for NumPy library. Pyplot is a state-based interface to a Matplotlib module which provides a MATLAB-like interface. There are various plots which can be used in Pyplot are Line Plot, Contour, Histogram, Scatter, 3D Plot, etc.

matplotlib.pyplot.phase_spectrum() Function:

The phase_spectrum() function in pyplot module of matplotlib library is used to plot the phase_spectrum. Generally, it compute the phase_spectrum of sequence and plotting is done.

Syntax: phase_spectrum(x, Fs=2, Fc=0, window=mlab.window_hanning, pad_to=None, sides=’default’, **kwargs)

Parameters: This method accept the following parameters that are described below:

x: This parameter is a sequence of data.

Fs : This parameter is a scalar. Its default value is 2.

window: This parameter take a data segment as an argument and return the windowed version of the segment. Its default value is window_hanning()

sides: This parameter specifies which sides of the spectrum to return. This can have following values : ‘default’, ‘onesided’ and ‘twosided’.

pad_to : This parameter contains the integer value to which the data segment is padded.

Fc: This parameter is also contains the integer value to offsets the x extents of the plot to reflect the frequency range. Its default value is 0

Returns: This returns the following:

spectrum :This returns the angle spectrum in radians.

freqs :This returns the frequencies corresponding to the elements in spectrum.

line : This returns the line created by this function.

The resultant is (spectrum, freqs, line)

Below examples illustrate the matplotlib.pyplot.phase_spectrum() function in matplotlib.pyplot:

Example-1:

# Implementation of matplotlib function 
import matplotlib.pyplot as plt 
import numpy as np 
   
np.random.seed(10**5) 
   
dt = 0.0001
Fs = 1 / dt 
  
zambiatek = np.array([24.40, 110.25, 20.05, 22.00, 61.90, 
                   7.80, 15.00, 22.80, 34.90, 57.30]) 
  
nse = np.random.randn(len(zambiatek)) 
r = np.exp(-zambiatek / 0.05) 
   
s = 0.1 * np.sin(2 * np.pi * zambiatek) + nse 
   
# plot phase_spectrum 
plt.phase_spectrum(s, Fs = Fs) 
plt.title('matplotlib.pyplot.phase_spectrum() function Example', 
                                             fontweight ="bold") 
  
plt.show() 

Output:

Example-2:

# Implementation of matplotlib function 
import matplotlib.pyplot as plt 
import numpy as np 
   
np.random.seed(0) 
   
dt = 0.01
Fs = 1 / dt 
t = np.arange(0, 10, dt) 
nse = np.random.randn(len(t)) 
r = np.exp(-t / 0.05) 
   
cnse = np.convolve(nse, r)*dt 
cnse = cnse[:len(t)] 
s = 0.1 * np.sin(2 * np.pi * t) + cnse 
   
# plot simple spectrum 
plt.subplot(2, 1, 1) 
plt.plot(t, s) 
plt.title('matplotlib.pyplot.phase_spectrum() function Example',  
                                             fontweight ="bold") 
  
plt.subplot(2, 1, 2) 
plt.phase_spectrum(s, Fs = Fs) 
  
plt.show() 