title: Extract columns with same names from multiple data frames [R]
body: <p>I am dealing with about 10 data frames that have the same column names, but different number of rows.  I would like to create a list of all columns with the same names.</p>
  
  <p>So, say i have 2 data frames with the same names.</p>
  
  <pre><code>a&lt;-seq(0,20,1)
  b&lt;-seq(20,40,1)
  c&lt;-seq(10,30,1)
  
  df.abc.1&lt;-data.frame(a,b,c)
  
  a&lt;-seq(20,50,1)
  b&lt;-seq(10,40,1)
  c&lt;-seq(30,60,1)
  
  df.abc.2&lt;-data.frame(a,b,c)
  </code></pre>
  
  <p>I know i can create a list from this data such as,</p>
  
  <pre><code>list(df.abc.1$a, df.abc.2$a)
  </code></pre>
  
  <p>but i don't want to type out my long data frame names and column names.</p>
  
  <p>I was hoping to do something like this,</p>
  
  <pre><code>list(c(df.abc.1, df.abc.2)$a)
  </code></pre>
  
  <p>But, it returns a list of df.abc.1$a</p>
  
  <p>Perhaps there could be a way to use the grep function across multiple data.frames?
  Perhaps a loop could accomplish this task?  </p>