title: How to rbind when only some of the columns match
body: <p>I have about 18 dataframes which are essentially frequency counts of the elements stored in the column Rptnames. They all have some different and some the same elements in the Rptnames columns so they look like this</p>
  
  <p>dataframe called GroupedTableProportiondelAll</p>
  
  <pre><code>Rptname    freq
  
  bob         4324234
  jane        433
  ham        4324
  tim         22
  
  dataframe called GroupedTableProportiondelLUAD
  
  Rptname     freq
  
  bob          987
  jane         223
  jonny        12
  jim          98092
  </code></pre>
  
  <p>I am trying to set up a table so that the Rptname becomes the column and each row is the frequencies. This is so that I can combine all the dataframes.</p>
  
  <p>I have tried the following</p>
  
  <pre><code>   GroupedTableProportiondelAll_T &lt;- as.data.frame(t(GroupedTableProportiondelAll))
      GroupedTableProportiondelLUAD_T &lt;- as.data.frame(t(GroupedTableProportiondelLUAD))
  
     total &lt;- rbind(GroupedTableProportiondelLUAD_T, GroupedTableProportiondelAll_T)
  </code></pre>
  
  <p>but I get the error 
      Error in rbind(deparse.level, ...) : 
    numbers of columns of arguments do not match</p>
  
  <p>So the question is 
  a) how can I do rbind (cbind would also do without transposing I suppose) so that the bind can happen without needing to match.<br>
  b) would merge be better here 
  c) in either is there a way to enter zero for empty values 
  d) P'raps there's a better way to do this like matrices which Im not really familiar with? I know its 4 questions but the central question's the same- how to bind when not all the rows or columns are matching</p>