linux 统计词频

统计一个文件中单词出现的频率, 以小写字母 空格组成

the day is sunny the the
the sunny is is
the 4
is 3
sunny 2
day 1

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• awk

awk中可使用关联数组, 类似于字典(无需定义, 自动扩展)

echo "" | awk 'BEGIN{arr["one"]=1;arr["two"]=2;arr["three"]=3}{for(key in arr)print key,arr[key]}'
three 3
two 2
one 1

awk脚本 BEGIN {运行前} END{运行后} {正文体}

cat words.txt | xargs -n 1 (每次只传递一个参数)| awk '{
    if($1 in data)
        data[$1] = data[$1] + 1
    else
        data[$1] = 1
 } END {for(str in data) print data[str],str}' | sort -rn(按数值大小反序) | awk '{print $2, $1}'