Question

我有一个序列文件，格式化为一行信息，后跟序列，例如：

someinformation length=50
JJJIJJJJJJJJJIJGIJJJJJJIJJIJJJJJIJJJJHHHHHFFFFFCCC
someotherinformation length=50
GEFE?BEDHCBBACEBHAFEBFEBFHFFDDDFD@@@
[...]

我想用下一行的实际长度替换长度= 50（可能是不同的数字）（没有下一行字符）。所以像这样：

sed -i "s/length=[0-9]+/length=length_next_line/" infile

是否可以在sed中获取下一行的长度？

使用20行input.txt文件进行了一次非常简单的时间测试（对于i在$（seq 10000）;使用input.txt＆gt; / dev / null; done）

Suku的回答：

real    0m54.932s
user    0m4.678s
sys 0m35.969s

埃德莫顿回答：

real    0m53.983s
user    0m3.789s
sys 0m33.574s

anubhava回答：

real    0m55.565s
user    0m5.929s
sys 0m36.049s

NeronLeVelu第一个回答和第二个回答：

real    0m54.688s
user    0m3.812s
sys 0m36.884s

real    0m55.066s
user    0m3.929s
sys 0m36.850s

Answer 1

import os, re import pandas as pd EMDASH = '—' with open('scrubbed_file','wt') as outfile: with open('original_file_location','rt') as infile: for line in infile: outfile.write(re.sub(EMDASH,'-',line)) df = pd.read_csv('scrubbed_file', engine='python', encoding='utf_16_le', names=['Country', 'Date', 'Delivery', 'Region'], delimiter='\t', quotechar='"', skiprows=2, skip_footer=2, thousands = ',')无法获得一条线的长度。您可以改为使用sed：

awk

Answer 2

$ cat input.txt
someinformation length=50
JJJIJJJJJJJJJIJGIJJJJJJIJJIJJJJJIJJJJHHHHHFFFFFCCC
someotherinformation length=50
GEFE?BEDHCBBACEBHAFEBFEBFHFFDDDFD@@@

$ awk '{ if(NR%2 == 1) {sub(/=[0-9]+$/,"=",$0); s=$0; next}  print s length($0) ORS $0 }' input.txt
someinformation length=50
JJJIJJJJJJJJJIJGIJJJJJJIJJIJJJJJIJJJJHHHHHFFFFFCCC
someotherinformation length=36
GEFE?BEDHCBBACEBHAFEBFEBFHFFDDDFD@@@

sub

awk

$0

next

awk

Answer 3

不，sed是针对各行的简单替换，就是全部。更有趣的是awk的工作：

vb.customize ["modifyvm", :id, "--memory", "4096"]
vb.customize ["modifyvm", :id, "--vram", "64"]
vb.customize ["modifyvm", :id, "--natdnshostresolver1", "on"]
vb.customize ["modifyvm", :id, "--autostart-enabled", "off"]
vb.customize ["modifyvm", :id, "--cpuexecutioncap", "40"]

Answer 4

仅适用于时间竞争的挑战： - ）

awk -F "length=" 'NF > 1 {Head=$1;next}
                  {print Head " length=" length($0) ORS $0}' YourFile

与其他调整

awk -F "length=" 'NF > 1 {printf "%s length=", $1;next}
                  {print length($0) ORS $0}' YourFile

与sed匹配后，我能获得下一行的长度吗？

4 个答案: