title: How to convert datatype:object to float64 in python?
body: <p>I am going around in circles and tried so many different ways so I guess my core understanding is wrong. I would be grateful for help in understanding my encoding/decoding issues.</p>
  
  <p>I import the dataframe from SQL and it seems that some datatypes:float64 are converted to Object. Thus, I cannot do any calculation. I fail to convert the Object back to float64.</p>
  
  <p><strong>df.head()</strong></p>
  
  <pre><code>Date        WD  Manpower 2nd     CTR    2ndU    T1  　　T2    　　T3    　　T4 
  
  2013/4/6    6   NaN     2,645   5.27%   0.29    407     533     454     368
  2013/4/7    7   NaN     2,118   5.89%   0.31    257     659     583     369
  2013/4/13   6   NaN     2,470   5.38%   0.29    354     531     473 　　383
  2013/4/14   7   NaN     2,033   6.77%   0.37    396     748     681     458
  2013/4/20   6   NaN     2,690   5.38%   0.29    361     528     541     381
  </code></pre>
  
  <p><strong>df.dtypes</strong></p>
  
  <pre><code>WD             float64
  Manpower       float64
  2nd             object
  CTR             object
  2ndU           float64
  T1              object
  T2              object
  T3              object
  T4              object
  T5              object
  
  dtype: object
  </code></pre>
  
  <p>SQL table:</p>
  
  <p><img src="https://i.stack.imgur.com/gdJKP.png" alt="enter image description here"></p>