title: julia dataframe - subsetting column by list of values
body: <pre><code>using DataFrames
  
  df = DataFrame(A = 1:10, B = 2:2:20)
  
  10x2 DataFrame
  | Row | A  | B  |
  |-----|----|----|
  | 1   | 1  | 2  |
  | 2   | 2  | 4  |
  | 3   | 3  | 6  |
  | 4   | 4  | 8  |
  | 5   | 5  | 10 |
  ...
  ...
  </code></pre>
  
  <p>is it possible to subset dataframe by using a list of values, something like</p>
  
  <pre><code>df[df[:A] .in [3,4], :]
  </code></pre>
  
  <p>if the list is small, this can by done by </p>
  
  <pre><code>df[(df[:A] .== 3) |  (df[:A] .== 4), :]
  </code></pre>
  
  <p>but I am wondering if there is way to do this for large list of values</p>