# wordfreq.awk --- print list of word frequencies

{
$0 = tolower($0) # remove case distinctions
# remove punctuation
gsub(/[^[:alnum:]_[:blank:]]/, "", $0)
for (i = 1; i <= NF; i++)
freq[$i]++
}

END {
sort = "sort -k 2nr"
for (word in freq)
printf "%s\t%d\n", word, freq[word] | sort
close(sort)
}