title: How to separate female and male without groupby() in python?
body: <p>It's a dataframes that each has Id, sex, age and so I.
  I first seperate the age with id and sex.`</p>
  
  <pre class="lang-python prettyprint-override"><code>    import numpy as np
      import pandas as pd
      age_distinct = titanic_df[['Sex','Age']].dropna()
      print age_distinct
  </code></pre>
  
  <p>get the result like this:</p>
  
  <pre class="lang-python prettyprint-override"><code>       Sex   Age
  0      male  22.0
  1    female  38.0
  2    female  26.0
  3    female  35.0
  4      male  35.0
  6      male  54.0
  7      male   2.0
  8    female  27.0
  9    female  14.0
  10   female   4.0
  11   female  58.0
  12     male  20.0
  13     male  39.0
  14   female  14.0
  15   female  55.0
  16     male   2.0
  18   female  31.0
  20     male  35.0
  21     male  34.0
  22   female  15.0
  23     male  28.0
  24   female   8.0
  25   female  38.0
  27     male  19.0
  30     male  40.0
  33     male  66.0
  34     male  28.0
  35     male  42.0
  37     male  21.0
  38   female  18.0
  ..      ...   ...
  856  female  45.0
  857    male  51.0
  </code></pre>
  
  <p>But I don't know the next step.
  How can I get a two set of data only include male and female</p>