Regex 基于第二个文本文件从文本文件中删除重复项
如何通过检查第二个文本文件(Regex 基于第二个文本文件从文本文件中删除重复项,regex,bash,unix,text,editor,Regex,Bash,Unix,Text,Editor,如何通过检查第二个文本文件(removethese.txt)来删除文本文件(main.txt)中的所有行。如果文件大于10-100mb,什么是有效的方法。[使用mac] 例子: 拆下这些线 removethese.txt 3 2 9 输出: output.txt 1 5 示例行(这些是我正在使用的实际行-顺序无关紧要): 使用grep: grep -vxFf removethese.txt main.txt >output.txt fgrep -vxf removethese.txt
removethese.txt
)来删除文本文件(main.txt
)中的所有行。如果文件大于10-100mb,什么是有效的方法。[使用mac]
例子:
拆下这些线
removethese.txt
3
2
9
输出:
output.txt
1
5
示例行(这些是我正在使用的实际行-顺序无关紧要):
使用
grep
:
grep -vxFf removethese.txt main.txt >output.txt
fgrep -vxf removethese.txt main.txt >output.txt
awk 'FNR==NR {a[$0];next} !($0 in a)' removethese.txt main.txt >output.txt
sed "s=^=/^=;s=$=$/d=" removethese.txt | sed -f- main.txt >output.txt
使用fgrep
:
grep -vxFf removethese.txt main.txt >output.txt
fgrep -vxf removethese.txt main.txt >output.txt
awk 'FNR==NR {a[$0];next} !($0 in a)' removethese.txt main.txt >output.txt
sed "s=^=/^=;s=$=$/d=" removethese.txt | sed -f- main.txt >output.txt
fgrep
已弃用<代码>fgrep--help显示:
不推荐调用为“fgrep”;改用“grep-F”
使用awk
(来自@fedorqui):
grep -vxFf removethese.txt main.txt >output.txt
fgrep -vxf removethese.txt main.txt >output.txt
awk 'FNR==NR {a[$0];next} !($0 in a)' removethese.txt main.txt >output.txt
sed "s=^=/^=;s=$=$/d=" removethese.txt | sed -f- main.txt >output.txt
使用sed
:
grep -vxFf removethese.txt main.txt >output.txt
fgrep -vxf removethese.txt main.txt >output.txt
awk 'FNR==NR {a[$0];next} !($0 in a)' removethese.txt main.txt >output.txt
sed "s=^=/^=;s=$=$/d=" removethese.txt | sed -f- main.txt >output.txt
如果removethese.txt包含特殊字符,则此操作将失败。为此,您可以:
sed 's/[^^]/[&]/g; s/\^/\\^/g' removethese.txt >newremovethese.txt
并在sed
命令中使用此newremovethese.txt。但这不值得努力,与其他方法相比,它太慢了
对上述方法进行的测试:
grep -vxFf removethese.txt main.txt >output.txt
fgrep -vxf removethese.txt main.txt >output.txt
awk 'FNR==NR {a[$0];next} !($0 in a)' removethese.txt main.txt >output.txt
sed "s=^=/^=;s=$=$/d=" removethese.txt | sed -f- main.txt >output.txt
sed
方法花费太多时间,不值得测试
使用的文件:
removethese.txt : Size: 15191908 (15MB) Blocks: 29672 Lines: 100233
main.txt : Size: 27640864 (27.6MB) Blocks: 53992 Lines: 180034
命令:grep-vxFf
|fgrep-vxf
|awk
所用时间:
0m7.966s
|0m7.823s
|0m0.237s
0m7.877s
|0m7.889s
|0m0.241s
0m7.971s
|0m7.844s
|0m0.234s
0m7.864s
|0m7.840s
|0m0.251s
0m7.798s
|0m7.672s
|0m0.238s
0m7.793s
|0m8.013s
|0m0.241s
平均值
0m7.8782s
0m7.8468s
0m0.2403s
该测试结果表明
fgrep
比grep
快一点
该awk
方法(来自@fedorqui)以优异的成绩通过了测试(0.2403秒
仅!!!)。
测试环境:
HP ProBook 440 G1 Laptop
8GB RAM
2.5GHz processor with turbo boost upto 3.1GHz
RAM being used: 2.1GB
Swap being used: 588MB
RAM being used when the grep/fgrep command is run: 3.5GB
RAM being used when the awk command is run: 2.2GB or less
Swap being used when the commands are run: 588MB (No change)
测试结果:
grep -vxFf removethese.txt main.txt >output.txt
fgrep -vxf removethese.txt main.txt >output.txt
awk 'FNR==NR {a[$0];next} !($0 in a)' removethese.txt main.txt >output.txt
sed "s=^=/^=;s=$=$/d=" removethese.txt | sed -f- main.txt >output.txt
使用
awk
方法。有两种标准方法:
使用grep
:
grep -vxFf removethese main
它使用:
以反转匹配-v
匹配整行,以防止,例如,-x
匹配像他
或你好
这样的行地狱公路
使用固定字符串,使参数保持原样,而不是解释为正则表达式-F
从另一个文件中获取图案。在这种情况下,请从-f
中删除这些
awk
:
$ awk 'FNR==NR {a[$0];next} !($0 in a)' removethese main
1
5
像这样,我们将每一行存储在中,并将它们移除到数组a[]
中。然后,我们读取main
文件,只打印数组中不存在的行。我喜欢@fedorqui使用awk进行设置,在设置中有足够的内存来容纳所有“删除这些”行:内存方法的简洁表达
但是,对于要删除的行的大小相对于当前内存来说是很大的场景,并且将该数据读入内存中的数据结构是失败或颤动的邀请,请考虑一种古老的方法:排序/加入
sort main.txt > main_sorted.txt
sort removethese.txt > removethese_sorted.txt
join -t '' -v 1 main_sorted.txt removethese_sorted.txt > output.txt
注:
- 这不会保留main.txt中的顺序:output.txt中的行将被排序
- 它需要有足够的磁盘来让sort完成它的工作(临时文件),并存储相同大小的输入文件的排序版本
- 让join的-v选项做我们想做的事情——从文件1中打印“不成对”,删除匹配项——有点意外
- 它不直接处理区域设置、排序、键等——它依赖于sort和join(-t,带一个空参数)的默认值来匹配排序顺序,而排序顺序恰好在我当前的机器上工作
以下是我发现的许多简单有效的解决方案:
您需要使用
Set complete
bash命令之一。100MB的文件可以在几秒钟或几分钟内解决
设置成员资格
$ grep -xc 'element' set # outputs 1 if element is in set
# outputs >1 if set is a multi-set
# outputs 0 if element is not in set
$ grep -xq 'element' set # returns 0 (true) if element is in set
# returns 1 (false) if element is not in set
$ awk '$0 == "element" { s=1; exit } END { exit !s }' set
# returns 0 if element is in set, 1 otherwise.
$ awk -v e='element' '$0 == e { s=1; exit } END { exit !s }'
设置相等值
$ diff -q <(sort set1) <(sort set2) # returns 0 if set1 is equal to set2
# returns 1 if set1 != set2
$ diff -q <(sort set1 | uniq) <(sort set2 | uniq)
# collapses multi-sets into sets and does the same as previous
$ awk '{ if (!($0 in a)) c++; a[$0] } END{ exit !(c==NR/2) }' set1 set2
# returns 0 if set1 == set2
# returns 1 if set1 != set2
$ awk '{ a[$0] } END{ exit !(length(a)==NR/2) }' set1 set2
# same as previous, requires >= gnu awk 3.1.5
$ wc -l set | cut -d' ' -f1 # outputs number of elements in set
$ wc -l < set
$ awk 'END { print NR }' set
设置交点
$ cat set1 set2 # outputs union of set1 and set2
# assumes they are disjoint
$ awk 1 set1 set2 # ditto
$ cat set1 set2 ... setn # union over n sets
$ cat set1 set2 | sort -u # same, but assumes they are not disjoint
$ sort set1 set2 | uniq
# sort -u set1 set2
$ awk '!a[$0]++' # ditto
$ comm -12 <(sort set1) <(sort set2) # outputs insersect of set1 and set2
$ grep -xF -f set1 set2
$ sort set1 set2 | uniq -d
$ join <(sort -n A) <(sort -n B)
$ awk 'NR==FNR { a[$0]; next } $0 in a' set1 set2
设置笛卡尔积
$ comm -23 <(sort subset | uniq) <(sort set | uniq) | head -1
# outputs something if subset is not a subset of set
# does not putput anything if subset is a subset of set
$ awk 'NR==FNR { a[$0]; next } { if !($0 in a) exit 1 }' set subset
# returns 0 if subset is a subset of set
# returns 1 if subset is not a subset of set
$ comm -23 <(sort set1) <(sort set2)
# outputs elements in set1 that are not in set2
$ grep -vxF -f set2 set1 # ditto
$ sort set2 set2 set1 | uniq -u # ditto
$ awk 'NR==FNR { a[$0]; next } !($0 in a)' set2 set1
$ p() { [ $# -eq 0 ] && echo || (shift; p "$@") |
while read r ; do echo -e "$1 $r\n$r"; done }
$ p `cat set`
# no nice awk solution, you are welcome to email me one:
# peter@catonmat.net
$ while read a; do while read b; do echo "$a, $b"; done < set1; done < set2
$ awk 'NR==FNR { a[$0]; next } { for (i in a) print i, $0 }' set1 set2
$ comm -12 <(sort set1) <(sort set2) # does not output anything if disjoint
$ awk '++seen[$0] == 2 { exit 1 }' set1 set2 # returns 0 if disjoint
# returns 1 if not
$ wc -l < set # outputs 0 if the set is empty
# outputs >0 if the set is not empty
$ awk '{ exit 1 }' set # returns 0 if set is empty, 1 otherwise
$whilereada;边读边做;做回显“$a$b”;完成
不相交集检验
$ comm -23 <(sort subset | uniq) <(sort set | uniq) | head -1
# outputs something if subset is not a subset of set
# does not putput anything if subset is a subset of set
$ awk 'NR==FNR { a[$0]; next } { if !($0 in a) exit 1 }' set subset
# returns 0 if subset is a subset of set
# returns 1 if subset is not a subset of set
$ comm -23 <(sort set1) <(sort set2)
# outputs elements in set1 that are not in set2
$ grep -vxF -f set2 set1 # ditto
$ sort set2 set2 set1 | uniq -u # ditto
$ awk 'NR==FNR { a[$0]; next } !($0 in a)' set2 set1
$ p() { [ $# -eq 0 ] && echo || (shift; p "$@") |
while read r ; do echo -e "$1 $r\n$r"; done }
$ p `cat set`
# no nice awk solution, you are welcome to email me one:
# peter@catonmat.net
$ while read a; do while read b; do echo "$a, $b"; done < set1; done < set2
$ awk 'NR==FNR { a[$0]; next } { for (i in a) print i, $0 }' set1 set2
$ comm -12 <(sort set1) <(sort set2) # does not output anything if disjoint
$ awk '++seen[$0] == 2 { exit 1 }' set1 set2 # returns 0 if disjoint
# returns 1 if not
$ wc -l < set # outputs 0 if the set is empty
# outputs >0 if the set is not empty
$ awk '{ exit 1 }' set # returns 0 if set is empty, 1 otherwise
$comm-12目标是您添加一些自己的代码,以显示您自己为解决此问题所做的研究工作。请查看grep
的手册页。@NorbertvanNobelen我尝试了几种解决方案,包括以下解决方案:,但我的列表很大且未排序。但该解决方案不过滤列表。通过Windows、Linux和Mac上提供的文本编辑器UltraEdit,可以使用UE脚本完成此操作,请参阅。@mofi UltraEdit是否处理大文件(10-100mb文件)?@shellter您介意建议一种更简单的方法吗?@shellter yap我测试了它(它可以正常工作)。。。但是你的建议非常有效,只需一行命令就可以完成..太棒了。。谢谢…如果你原来的解决方案有效,你应该把它留在你的答案里。我怀疑echo$(grep something output.txt)>output.txt
是否会覆盖output.txt的现有内容,但时间太晚了,可能会起作用。在任何情况下,我都会推荐grep-vFf…
解决方案。祝大家好运@Sheller即使有效,越晚越好。为了澄清,之前的grep覆盖了内容,这是有意的…@sheller否,output.txt被修改(sed-i
)。它不会将任何输出打印到屏幕上,它会删除output.txt
中的那些行。我以前尝试过grep-vFf从另一个答案中删除这些行main.txt>output.txt
,处理一个7mb的文件需要4-6个小时。你认为awk是什么