diff --git a/02_word_freq/src/plotfreq.r b/02_word_freq/src/plotfreq.r
index 723d903..d5a76fc 100755
--- a/02_word_freq/src/plotfreq.r
+++ b/02_word_freq/src/plotfreq.r
@@ -1,9 +1,16 @@
 #! /usr/bin/Rscript
 
 args <- commandArgs(trailingOnly = TRUE)
+if (length(args) > 0){
+    outfile = args[1]
+} else {
+    outfile = "freqPlot.pdf"
+}
 
-lwords <- lapply(args, readLines)
-words <- unlist(lwords)
+f <- file("stdin")
+open(f)
+words <- readLines(f)
+close(f)
 head(words)
 
 logWordFreq <- sort(log(table(words)),decreasing = TRUE)
@@ -14,7 +21,9 @@
 logFreqFreqRank <- log(1:length(logFreqFreq))
 head(logFreqFreq)
 
-pdf()
+print(paste("Save plot to", outfile))
+a4width <- 8.3
+pdf(outfile, width=a4width, height=a4width/2)
 par(mfcol=c(1,2))
 plot(logWordFreqRank,
      logWordFreq,
@@ -26,4 +35,3 @@
      type='l',
      xlab="log rank",
      ylab="log frequency of word frequency")
-dev.off()
diff --git a/02_word_freq/src/wordify.sh b/02_word_freq/src/wordify.sh
index 34b3937..6b852ea 100755
--- a/02_word_freq/src/wordify.sh
+++ b/02_word_freq/src/wordify.sh
@@ -1,7 +1,7 @@
 #! /bin/bash
 
 # concatenate all input files
-cat $* |
+cat - |
 
 # remove BOM from UTF-8
 sed '1 s/^\xef\xbb\xbf//' |