title: Nan values when plotting Matplotlib
body: <p>Hi i am trying to display a large merged data set into a scatter plot graph to find the relationship between The gdp per capita and number of kids. The dataframe looks someting like this. How do i remove the rows with Nan Values and plot the scatter? Or do i just plot the graph straight and it will ignore all rows with NaN value? Any help would be great thanks :) Also , when calculating the mean of the second and third column , do i show the result on another column?</p>
  
  <pre><code>Country | Number of kids | GDP per capita
    A     |      4         |    2345
    B     |      2         |    2156
    C     |     NaN        |    1156
    D     |     5          |    958
    E     |     NaN        |    NaN
    F     |     8          |    NaN
  .
  .
  .
   Z      |     3          |    2 
  </code></pre>