title: Convert character variable column to vector
body: <p>Have a .csv with 4 columns of values:</p>
  
  <pre><code>data&lt;-read.csv("C:\\Users\\mtatange\\Desktop\\Dataset.csv")
  A         B        C        D   
  1         1       NA        1   
  2         2        4        1   
  3         3        6        4   
  4        NA        8        5
  
  data$E&lt;-do.call(paste,c(data[c("A","B","C","D")], sep=""))
  data
  A         B        C        D       E        
  1         1       NA        1      11NA1 
  2         2        4        1      2241
  3         3        6        4      3364 
  4        NA        8        5      4NA85
  
  summary(data)
  E
  Length: 4
  Class: Character
  Mode: Character
  </code></pre>
  
  <p>I need column "E" to be a vector, it cannot stay as a character variable. I tried:</p>
  
  <pre><code>data$E[is.na(a$E)]&lt;-0
  </code></pre>
  
  <p>But that still left the column as a character variable. How do I convert the column to a vector variable?</p>