用另一个文件中指定的值替换字段

Question

我有一个文件,其中包含单词之间的映射.我必须引用该文件,并将这些单词替换为某些文件中的映射单词.例如,下面的文件具有映射的单词表

1.12.2.4               1
1.12.2.7               12
1.12.2.2               5
1.12.2.4               4
1.12.2.6               67
1.12.2.12              5

我将有许多具有这些关键词的文件(1.12.2.*).我想搜索这些关键词,并将这些词替换为从该文件中获取的相应映射.如何在shell中执行此操作.假设一个文件包含以下行说

The Id of the customer is 1.12.2.12. He is from Grg. 
The Name of the machine is ASB
The id is 1.12.2.4. He is from Psg.

执行脚本后,数字"1.12.2.12"和"1.12.2.4"应替换为5和4(从主文件中引用).谁能帮我吗？

Answer 1

一种方式使用GNU awk:

awk 'FNR==NR { array[$1]=$2; next } { for (i in array) gsub(i, array[i]) }1' master.txt file.txt

结果:

The Id of the customer is 5. He is from Grg.
The Name of the machine is ASB
The id is 4. He is from Psg.

要将输出保存到文件:

awk 'FNR==NR { array[$1]=$2; next } { for (i in array) gsub(i, array[i]) }1' master.txt file.txt > name_of_your_output_file.txt

说明:

FNR==NR { ... }   # FNR is the current record number, NR is the record number
                  # so FNR==NR simply means: "while we process the first file listed
                  # in this case it's "master.txt"
array[$1]=$2      # add column 1 to an array with a value of column 2
next              # go onto the next record

{                 # this could be written as: FNR!=NR
                  # so this means "while we process the second file listed..."
for (i in array)  # means "for every element/key in the array..."
gsub(i, array[i]) # perform a global substitution on each line replacing the key
                  # with it's value if found
}1                # this is shorthand for 'print'

添加单词边界会使匹配更严格:

awk 'FNR==NR { array[$1]=$2; next } { for (i in array) gsub("\\<"i"\\>", array[i]) }1' master.txt file.txt

Answer 2

你可以为你sed写一个sed脚本:

映射:

cat << EOF > mappings
1.12.2.4               1
1.12.2.7               12
1.12.2.2               5
1.12.2.4               4
1.12.2.6               67
1.12.2.12              5
EOF

输入文件:

cat << EOF > infile
The Id of the customer is 1.12.2.12. He is from Grg. 
The Name of the machine is ASB
The id is 1.12.2.4. He is from Psg.
EOF

根据映射生成脚本(GNU sed):

sed -r -e 's:([^ ]*) +(.*):s/\\b\1\\b/\2/g:' mappings

输出:

s/\b1.12.2.4\b/1/g
s/\b1.12.2.7\b/12/g
s/\b1.12.2.2\b/5/g
s/\b1.12.2.4\b/4/g
s/\b1.12.2.6\b/67/g
s/\b1.12.2.12\b/5/g

与另一个sed(GNU sed)评估:

sed -r -e 's:([^ ]*) +(.*):s/\\b\1\\b/\2/g:' mappings | sed -f - infile

输出:

The Id of the customer is 5. He is from Grg. 
The Name of the machine is ASB
The id is 1. He is from Psg.

请注意,映射被视为正则表达式,例如,dot(.)可以表示任何字符,并且可能需要在映射文件中或生成sed脚本时转义.