title: mutate/transform in R dplyr (Pass custom function)
body: <p>I am using the new package , dplyr and facing some difficulties.</p>
  
  <pre><code>mutate(df,isOdd=digit%%2) or transform(df,isOdd=digit%%2)
  </code></pre>
  
  <p>Both of which work perfectly.</p>
  
  <p>I am asking a question on passing custom method.</p>
  
  <pre><code>IsItOdd &lt;- function(x) {
    if(x%%2==0)
       result&lt;-"even"
    else
       result&lt;-"odd"
    return(result)
  }
  
  transform(df,isOdd=IsItOdd(digit))
  </code></pre>
  
  <p>This doesnt work because the whole column of all the digit is passed to the function. 
  Is there a way to make this work by just passing that one cell to the function instead of the whole column ?</p>