sed:从文件中删除字母数字

时间:2010-12-13 20:30:12

标签: sed text-formatting

我的文件包含大量文字,我想要删除所有字母数字。

Example of words to be removed:

gr8  
2006  
sdlfj435ljsa  
232asa  
asld213  
ladj2343asda
asd!32  

我能做到这一点的最佳方式是什么?

4 个答案:

答案 0 :(得分:6)

如果你想删除所有由字母和数字组成的单词,只留下由所有数字或所有字母组成的单词:

sed 's/\([[:alpha:]]\+[[:digit:]]\+[[:alnum:]]*\|[[:digit:]]\+[[:alpha:]]\+[[:alnum:]]*\) \?//g' inputfile

示例:

$ echo 'abc def ghi 111 222 ab3 a34 43a a34a 4ab3' | sed 's/\<\([[:alpha:]]\+[[:digit:]]\+[[:alnum:]]*\|[[:digit:]]\+[[:alpha:]]\+[[:alnum:]]*\) \?//g'
abc def ghi 111 222

答案 1 :(得分:2)

假设您希望从示例文本中获得的唯一输出是2006,并且每行有一个单词:

 sed '/[[:alpha:]]\+/{/[[:digit:]]\+/d}' /path/to/alnum/file

输入

$ cat alnum
gr8
2006
sdlFj435ljsa
232asa
asld213
ladj2343asda
asd!32
alpha

输出

$ sed '/[[:alpha:]]\+/{/[[:digit:]]\+/d}' ./alnum
2006
alpha

答案 2 :(得分:0)

如果目标实际上是删除所有字母数字单词(完全由字母和数字组成的字符串),则此sed命令将起作用。它没有替换所有字母数字字符串。

sed 's/[[:alnum:]]*//g' < inputfile

请注意,alnum以外的其他字符类也可用(请参阅man 7 regex)。

对于给定的示例数据,这只留下6个空行和一个!(因为这是示例数据中唯一的非字母数字字符)。这实际上是你想要做的吗?

答案 3 :(得分:0)

AWK解决方案:

BEGIN { # Statement that will be executed once at the beginning.
    FS="[ \t]" # Set space and tab characters to be treated as word separator.
}
# Code below will execute for each line in file.
{
    x=1  # Set initial word index to 1 (0 is the original string in array)
    fw=1 # Indicate that future matched word is a first word. This is needed to put newline and spaces correctly.
    while ( x<=NF )
    {
        gsub(/[ \t]*/,"",$x) # Strip word. Remove any leading and trailing white-spaces.
        if (!match($x,"^[A-Za-z0-9]*$")) # Print word only if it does not match pure alphanumeric set of characters.
        {
            if (fw == 0)
            {
                printf (" %s", $x) # Print the word offsetting it with space in case if this is not a first match.
            }
            else
            {
                printf ("%s", $x) # Print word as is...
                fw=0 # ...and indicate that future matches are not first occurrences
            }
        }
        x++ # Increase word index number.
    }
    if (fw == 0) # Print newline only if we had matched some words and printed something.
    {
        printf ("\n")
    }
}

假设您在script.awk' and data in data.txt , you have to invoke awk中设置了此脚本:

awk -f ./test.awk ./data.txt

对于您的文件,它将产生:

asd!32

对于像这样的更复杂的案例:

gr8
2006
sdlfj435ljsa
232asa  he!he lol
asld213  f
ladj2343asda
asd!32  ab acd!s

......它会产生这个:

he!he
asd!32 acd!s

希望它有所帮助。 祝你好运!