Shell command to delete \n on 1 out of 2 line on a file

Question

I'm looking for a shell command to delete the return chariot on one line out of two. I have a file like this :

1.32640997
;;P
1.14517534
;;P
1.16120958
;;P
...

And I would like something like this:

1.32640997;;P
1.14517534;;P
1.16120958;;P
...

Is it possible? Thanks

janos · Answer 1 · 2016-08-02T08:46:12.363

3

paste -d '' - - < file

paste -d '\0' - - < file

paste produces two columns from stdin with - - as parameters, 3 columns with - - - as parameters, and so on.

-d is to specify a column separator, use '\0' for no separator.

perl -ne 'chomp($prev = $_); print $prev, scalar <>' < file

edited Aug 02 '16 at 08:46

answered Aug 02 '16 at 07:54

janos

score 2 · Accepted Answer · edited Aug 02 '16 at 08:02

2

$ awk '{printf "%s%s",$0,(NR%2==0?ORS:"")}' File
1.32640997;;P
1.14517534;;P
1.16120958;;P

This prints each line followed by nothing for odd lines or followed by the output record separator for even lines.

This works by reading in lines in pairs:

$ sed 'N; s/\n//' File
1.32640997;;P
1.14517534;;P
1.16120958;;P

N reads in the next line and s/\n// removes the newline.

edited Aug 02 '16 at 08:02

janos

answered Aug 02 '16 at 07:50

John1024

For the record, this is better than my `paste` solution, because sed and awk are more widely available (for example no `paste` in Git Bash if I recall correctly) – janos Aug 02 '16 at 08:03

score 0 · Answer 3 · answered Aug 02 '16 at 08:13

0

Using xargs:

xargs -n 2 -d '\n' printf '%s%s\n' <file

answered Aug 02 '16 at 08:13

user1934428

3 Answers3