title: Find the peak values from data
body: <p>I plot the frequency on x-axis and intensity on y-axis via matplotlib. </p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  from scipy.signal import argrelmax, argrelmin
  
  data = np.loadtxt('pr736024.dat')
  z=np.array(data[:,1])   
  y = (z-z.min())/(z.max()-z.min()) #for normalization
  
  x = np.loadtxt('frq.txt')
  
  plt.plot(x,y, linewidth = 0.2, color='black')
  plt.plot(x,indexes, "o")
  plt.show()
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/uvZDT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uvZDT.png" alt="enter image description here"></a></p>
  
  <p>I want to get the intensity value at the peaks (there are 6 peaks which can be seen in plot). How can I achieve this?</p>