使用来自另一个文件的随机数据更新源文件中的数据

Question

我在源文件中有数据，如下所示(文件.txt(

N4*WALTER*WHITE~DMG*D8*19630625~N4*JESSI*PINKMAN*15108~

输入命令：(N4 = 段标识符，1 = 位置，ref.txt=参考文件(

N4*1*ref.txt

参考.txt有如下数据

BILL
LEONARDO
BALE
BRAD
PITT

我有下面的代码，它在 N4 的位置 x(输入(显示数据

identifier=N4
position=1
refile=ref.txt
awk -F[*~] -v id="$identifier" -v pos="$position" 
   'id { for (i=1; i<=NF; i++)
         if ($i == id) {
             if (i+pos <= NF)
                 print $(i+pos)
             else
                 print "invalid position"
         }
       }
    ' file.txt
WALTER
JESSI

identifier=N4
position=2
refile=ref.txt
awk -F[*~] -v id="$identifier" -v pos="$position" 
   'id { for (i=1; i<=NF; i++)
         if ($i == id) {
             if (i+pos <= NF)
                 print $(i+pos)
             else
                 print "invalid position"
         }
       }
    ' file.txt
WHITE
PINKMAN

现在我如何在上面的代码中集成 ref.txt 以更新文件中的 WALTER 和 JESSI.txt以及位于 ref.txt 文件中的随机文本。

我知道 shuf 命令从 ref.txt 提供随机数据，但不确定如何将其集成到上面的 awk 命令中。

shuf -n -1 ref.txt

预期输出：文件.txt(N4 段的位置 1 数据(使用来自 ref 的随机文本进行更新.txt

N4*BALE*WHITE~DMG*D8*19630625~N4*PITT*PINKMAN*15108~

Answer 1

好吧，我可以在 bash 中做到这一点，但循环while read会很慢：

# recreate the input files
cat <<EOF >file.txt
N4*WALTER*WHITE~DMG*D8*19630625~N4*JESSI*PINKMAN*15108~
EOF
cat <<EOF >input
N4*1*ref.txt
EOF
cat <<EOF >ref.txt
BILL
LEONARDO
BALE
BRAD
PITT
EOF
# read the input
IFS='*' read  -r segment position reference_file <input
{
  # for each line
  while IFS='*' read -r -d'~' -a data; do
    # if the segment id is the segmend
    if [ "${data[0]}" = "$segment" ]; then
        # update the data
        data[$position]=$(shuf -n1 "$reference_file")
    fi
    # and output the data
    ( IFS=*; printf "%s~" "${data[*]}"; )
  done
  # append a newline on the end
  echo
} < file.txt

我想尝试用sed来迭代段，但最终预处理sed输入。下面是，有评论：

IFS='*' read  -r segment position reference_file <input
# remove the nelwine from input
# and substitute each `~` with a newline
# so we can nicely process the file in sed
<file.txt tr -d 'n' | tr '~' 'n' >tmp.txt
# count of segments inside input we are interested in
segmentscnt=$(
  grep "^${segment}*" tmp.txt | wc -l
)
# generate single line with random words from reference_file
# words separated by `*`
# the count of words should that many as many are there
# segments we are interested in the input file
randoms=$(
  while shuf -n1 "$reference_file"; do :; done | 
  head -n"$segmentscnt" |
  tr 'n' '*'
)
sed -n "
  # the first line should be random words from referencefile
  # load it to hold space
  1{
    h
    d
  }
  # if this is our segment
  /^$segment*/{
    # append random words to our pattern space
    G
    # remember as many fields as the position we want to insert
    # each one word more
    # remember rest of line
    # remember first word from randoms that were inserted from hold space
    # then just substitute the words in proper order
    s/^(([^*]**){$position})[^*]*([^n]*)n([^*]*)*.*/143/
    # remove the first word from hold space
    x
    s/^([^*]*)*//
    x
  }
  p
# the first input are the random words separated by *
# the words are on a single line
# than the input file
" - <<<"$randoms" tmp.txt |
# then replace newlines with `~`. 
# also append a newline with echo
# as it will be missing
tr 'n' '~'; echo