title: Python Numpy arrays, Vlookup like function
body: <p>I would like to ask for your help. The problem in steps.
  1. Import two excel files into Python Data frames - so far no problem
  2. Transferring the data frames into numpy arrays.
  3. Create a VLOOKUP function in python, with the arrays. Both arrays have a key in the first column, which is unique and can be used for matching. The two tables include data, which is correct in one table but not in the other one. I would like to overwrite values in the table where values are wrong from the table where values are correct (I know, which table is has the right values...)</p>
  
  <p>Is there a more numpy way to do it;</p>
  
  <h1>So far the code I wrote:</h1>
  
  <pre><code>import pandas as pd
  
  df=pd.DataFrame()
  
  s = pd.read_excel("C:\a.xlsx")
  
  r = pd.read_excel("C:\b.xlsx")
  
  z=s.values
  
  t = r.values
  </code></pre>
  
  <h1>Here matching the two arrays, and overwriting the value</h1>
  
  <pre><code>for i in z:
  
      for j in t:
  
          if z[i, 0] == t[j, 0]:
  
              t[i, 41] = z[j, 5]
  </code></pre>