Convert vertical text into horizontal in shell

Question

I just pondered upon this problem while executing some tasks in shell.

How can I convert a .txt file which contains text in the following format[vertical direction]:

H
e
l
l
o

W
o
r
l
d

Note: The line without any letter contains a space and EOL

I need to convert to:

Hello World

I tried the following command: cat file1.txt |tr '\n' ' ' >file2.txt

Output:

H e l l o  W o r l d

How can I proceed further? Sorry, if this question has already appeared. If so, please provide me the link to the solution or any command for the work around.

Answer 1

You are replacing the new lines with spaces. Instead, remove them with -d:

$ echo "H
> e
>                   # <- there is a space here
> W
> o" | tr -d '\n'
He Wo

With a file:

tr -d '\n' < file   # there is no need to `cat`!

Problem here is that the last new line is removed, so the result is POSIXly a 0-lines file.