title: Columnbind ff data frames in R
body: <p>i try to work with the ff package. In this context i try to cbind two ff dataframes. I found a solution to combine a ffdf with a ff vector but how do i combine to ffdf. Here my code for combining ffdf with ff vector:</p>
  
  <pre><code>library(ff)
  ## read Bankfull flow##
  setwd(wd)
  bf &lt;- read.csv.ffdf(file="G_BANKFULL_km3month.csv",header=TRUE)
  ## read river discharge global, monthly vlaues 1971-2000##
  memory.limit(size=16000)   # increase working memory
  dis &lt;- read.table.ffdf(file='RIVER_AVAIL_7100_WG22.txt', header=T, sep="\t", dec=".")
  ##read bankfull values as ff object##
  bfvalues &lt;- ff(bf[,2])
  ##combination of bf and dis ( see test &lt;- cbind(dis,bf$VALUE))
  dis_bf &lt;- do.call('ffdf', c(physical(dis), list(bfvalues=bfvalues)))
  </code></pre>
  
  <p>Thanks a lot for your help</p>