从 txt 文件中提取文本

Question

我有一个包含记录的 txt 文件。记录遵循以下模式：

six lines, blank space, six lines, .....就像这个例子：

string line 1
string line 2
string line 3
string line 4
string line 5 (year format yyyy)
string line 6 (can use several lines)
<blank space> (always a blank space when a new txt block begins)
string line 1
string line 2
string line 3
string line 4
string line 5 (year format yyyy)
string line 6

这是一个合适的例子：我需要标题（第 2 行）和年份（第 5 行）

Hualong Yu, Geoffrey I. Webb,
Adaptive online extreme learning machine by regulating forgetting factor by concept drift map,
Neurocomputing,
Volume 343,
2019,
Pages 141-153,
ISSN 0925-2312,
https://doi.org/10.1016/j.neucom.2018.11.098.
https://www.sciencedirect.com/science/article/pii/S0925231219301572

Antonino Feitosa Neto, Anne M.P. Canuto,
EOCD: An ensemble optimization approach for concept drift applications,
Information Sciences,
Volume 561,
2021,
Pages 81-100,
ISSN 0020-0255,
https://doi.org/10.1016/j.ins.2021.01.051.
https://www.sciencedirect.com/science/article/pii/S002002552100089X

我想提取第 2 行中的字符串和第 5 行中的所有文本块（以空格分隔），将其保存到另一个 txt 文件作为此输出：

string line2 , yyyy

我没有经验 linux shell 所以我在这里寻求一些意见来帮助我完成这项任务。

谢谢

Answer 1

类似于：

perl -00 -nE 'my @ln = (split /,\n/)[1,4]; say join(",", @ln)'  input.txt > output.txt

至少应该作为一个起点。一次阅读一个段落，分成几行，然后在同一行上打印您要查找的两个段落，并用逗号分隔。

Answer 2

如果您不关心第 5 行中的尾随逗号，只需执行以下操作：

 awk '{print , }' RS= FS='\n' input > output

这假定分隔记录的空白行确实是完全空白的并且不包含任何空格。如果该行中有任何空格，您需要预过滤数据以将其删除。

例如：

$ cat input
Hualong Yu, Geoffrey I. Webb,
Adaptive online extreme learning machine by regulating forgetting factor by concept drift map,
Neurocomputing,
Volume 343,
2019,
Pages 141-153,
ISSN 0925-2312,
https://doi.org/10.1016/j.neucom.2018.11.098.
https://www.sciencedirect.com/science/article/pii/S0925231219301572

Antonino Feitosa Neto, Anne M.P. Canuto,
EOCD: An ensemble optimization approach for concept drift applications,
Information Sciences,
Volume 561,
2021,
Pages 81-100,
ISSN 0020-0255,
https://doi.org/10.1016/j.ins.2021.01.051.
https://www.sciencedirect.com/science/article/pii/S002002552100089
$ awk '{print , }' RS= FS='\n' input
Adaptive online extreme learning machine by regulating forgetting factor by concept drift map, 2019,
EOCD: An ensemble optimization approach for concept drift applications, 2021,

从 txt 文件中提取文本

Extracting text from a txt file

linux

shell

script