title: Twitter: Get followers from multiple users at once
body: <p>I am working on a project where I need to find the reach of some social events. I want to know how many people who were exposed to comments on a festival called Tinderbox in Denmark.
  What I do is to get the statusses on Twitter including the word "tinderbox" on the language danish. Then I want to extract the number of followers from these screennames. So the first part of my code is given by:</p>
  
  <pre><code>library("twitteR")
  setup_twitter_oauth(consumer_key,consumer_secret,access_token,access_secret)
  1
  #get data
  TB&lt;-searchTwitter("tinderbox", lan="da", n=10000)
  #put into a dataframe
  df &lt;- do.call("rbind", lapply(TB, as.data.frame))
  </code></pre>
  
  <p>My thought is to make use of the same output as in the example below, that is to 
  get followersCount directly from the twitter data. 
  The example is found here on stackoverflow. But I dont know how to do it to solve my purpose (<a href="https://stackoverflow.com/questions/17301119/fetching-large-number-of-followers-and-followees-in-r">fetching large number of followers and followees in R</a>)</p>
  
  <pre><code>library(twitteR)
  user &lt;- getUser("krestenb")
  followers &lt;- user$getFollowers()
  b &lt;- twListToDF(followers)
  f_count &lt;- as.data.frame(b$followersCount)
  u_id &lt;- as.data.frame(b$id)
  u_sname &lt;- as.data.frame(b$screenName)
  u_name &lt;- as.data.frame(b$name)
  final_df &lt;- cbind(u_id,u_name,u_sname,f_count)
  sort_fc &lt;- final_df[order(-f_count),]
  colnames(sort_fc) &lt;- c('id','name','s_name','fol_count')
  </code></pre>
  
  <p>My problem is that I cannot simply use a vector of user-name in the followers &lt;- &lt;- user$getFollowers(), by extracting the list of screennames from the df$screenName. </p>
  
  <p>So my thought was that maybe I needed to do a loop with all the different screennames. But I do not know how to do this.</p>
  
  <p>I have that I have painted the picture of what I want to get, and how I thought/think I can get there. </p>
  
  <p>Help is much apreciated as the festival is due this weekend. </p>