title: Pearson Correlation after Normalization
body: <p>I want to normalize my data and compute a pearson correlation. If I try this without normalization it works. With normalization I get this error message: AttributeError: 'numpy.ndarray' object has no attribute 'corr'
  What can I do to solve this problem?</p>
  
  <pre><code>import numpy as np
  import pandas as pd
  
  
  filename_train = 'C:\Users\xxx.xxx\workspace\Dataset\!train_data.csv'
  names = ['a', 'b', 'c', 'd', 'e', ...]
  df_train = pd.read_csv(filename_train, names=names)
  
  from sklearn.preprocessing import Normalizer
  normalizeddf_train = Normalizer().fit_transform(df_train)
  
  #pearson correlation
  pd.set_option('display.width', 100)
  pd.set_option('precision', 2)
  print(normalizeddf_train.corr(method='pearson'))
  </code></pre>