title: column with multiple values in data.frame
body: <p>I would like to make a data.frame in R with some columns having multiple values (same number of variables for all rows). For example, here is a data frame with two columns (cars and price), note that column price has three values for each row.</p>
  
  <pre><code>cars price
  
  F    1000,2000,3000
  
  GM   2000, 500, 1000
  </code></pre>
  
  <p>The second question:</p>
  
  <p>Now I want to apply the same function to each value in the price column, how can I do that? Let's say I want to create another column with doubled values of price column.</p>