This question already has answers here:
Remove everything after the first / including the first / for each line
(3 answers)
Closed 8 years ago.
I'm trying to use command line to find and replace some text. I have a file with a few million lines that are similar to this:
Something-Here/Grafton-WV</loc>
More-Information/Claremore-OK</loc>
This-Is-It/Seminole-OK</loc>
Your-Company/Lunenburg-MA</loc>
What I need to do is remove the slash and everything after it. I've done wildcard find/replace before but I'm not sure what command would need to be used to start at the slash and continue until the end of the line.
Here's what the output should be:
Something-Here
More-Information
This-Is-It
Your-Company
The following one-liner could work for you:
perl -pe 's{/.*}{}' file.txt
Explanation:
Switches:
-p: Creates a while(<>){...; print} loop for each “line” in your input file.
-e: Tells perl to execute the code on command line.
Code:
s{/.*}{}: Remove all characters after the first forward slash from the line
This is usually done with sed:
sed 's|/.*||' file.txt > newfile.txt
Related
This question already has answers here:
How to replace a whole line with sed?
(6 answers)
Closed 1 year ago.
hello I am needing help to be able to replace a line of a file with ssh and sed.
The problem is the following I have a string for example:
mystring = 1234
The point is that after the = it is not always 1234, so I am not able to replace that line.
sed -i 's/mystring =/mystring=1234/g' file.ini
when I run it two things happen:
mystring = 12341234 (add the numbers)
mystring = 123412345 (don't delete it, leave it there)
and if the variable (sed -i 's/mystring=/mystring=1234/g' file.ini) is executed more than twice, what it does is add the number at the end.
That is why I need to replace the entire line, something that if it is done more than 1 you see it will always remain the same, and if it is different, change it to the value that is set in the command.
From already thank you very much.
You can always match and replace the whole line:
sed -i 's/^mystring=.*/mystring=newvalue/' yourfile
.* in a regular expression matching any number of characters, including none.
You can also change all lines containing a certain pattern:
sed -i '/^mystring=/c\
mystring=newvalue' yourfile
Or with GNU sed:
sed -ie '/^mystring=/c\' -e 'mystring=newvalue' yourfile
This question already has answers here:
Why does my tool output overwrite itself and how do I fix it?
(3 answers)
Closed 1 year ago.
I have the following line:
>A_1000
ACTTTCGATCTCTTGTAGATCTGTTCTC...CAC
ACTTTCGATCTCTTGTAGATCTGTTCTC...CAC
I would like to convert the first line as follows:
>Initialword/A_1000/Finalword
ACTTTCGATCTCTTGTAGATCTGTTCTC...CAC
ACTTTCGATCTCTTGTAGATCTGTTCTC...CAC
I found a similar question that did allow me to append the end and the beginning as I needed (Add words at beginning and end of a FASTA header line with sed). However, it adds the Finalword to the next line.
I ran the following:
sed 's%^>(.*)%>Initialword/\1/Finalword%' input.fasta > output.fasta
Which returns:
>Initialword/A_0101M/Finalword
ACTTTCGATCTCTTGTAGATCTGTTCTC...CACM
ACTTTCGATCTCTTGTAGATCTGTTCTC...CACM
But in the Fasta file it looks like:
>Initialword/A_0101
/Finalword
ACTTTCGATCTCTTGTAGATCTGTTCTC...CAC
ACTTTCGATCTCTTGTAGATCTGTTCTC...CAC
How can I fix this to just add the text to the beginning and end of the header? What is the M at the end of each line in the file?
Thank you
First convert your file and then use GNU sed:
dos2unix <input.fasta | sed -E 's%^>(.*)%>Initialword/\1/Finalword%' >output.fasta
This question already has answers here:
How to escape the ampersand character while using sed
(3 answers)
Closed 2 years ago.
My config file looks like:
KEY1=VALUE1
URL=https://drive.google.com/uc?export=download&id=myhash
KEY3=VALUE3
I'm trying to use sed to replace the URL value with another one. I got to the following:
sed -i.bak 's#URL=.*#URL=https://drive.google.com/uc?export=download&id=mynewhash#g' file.txt
But that doesn't seem to work, as I'm getting:
URL=https://drive.google.com/uc?export=downloadURL=https://drive.google.com/uc?export=download&id=mynewhash=myhash
What am I missing? Thanks
& is a special character in the replacement string provided to the s command of sed. It represents the string that matches the entire regex used to search (URL=.* in your example).
In order to represent itself it needs to be escaped with \:
sed -i.bak 's#URL=.*#URL=https://drive.google.com/uc?export=download\&id=mynewhash#g' file.txt
Type man sed in your terminal to read its documentation or read the documentation of sed online.
This question already has answers here:
Reverse input order with sed
(6 answers)
Closed 4 years ago.
For example, we have:
This is the song that doesn`t end
What sed command will turn it into this?
end doesn`t that song the is This
I've found only how to reverse lines in a file (a.k.a. tac):
sed -n '1!G;h;$p'
This might work for you (GNU sed):
sed -r 'G;:a;s/^(\S+)(\s*)(.*\n)/\3\2\1/;ta;s/\n//' file
Append a newline as a delimiter. Split the current line into three and prepend the first word, the following space and the remainder of the line following the newline in that order. Iterate until the pattern matching fails and then remove the introduced newline.
Could you please try following and let me know if this helps you.
awk '{for(i=NF;i>0;i--){printf("%s%s",$i,(i>1?OFS:ORS))}}' Input_file
This question already has answers here:
Shell variables in sed script [duplicate]
(5 answers)
Closed 8 years ago.
I want to delete words into a line. For example:
I want to delete one word in this line
And I want to delete 'one' to obtain:
I want to delete word in this line
By passing the word through a variable. So far I have got:
WORD=one ; sed -n 's/"$WORD"//g' file.txt > newfile.txt
But, it doesn't do anything. Why not? And how can I make it work?
WORD=one ; sed -e "s/$WORD//g" file.txt > newfile.txt
the key moment is variable expansion. You have to be careful though because shell variable expansion may be sometimes not what you want. In hard cases you have to do something like this:
EXPANDVAR=one; NOEXPANDVAR=another; sed -e 's/'"$EXPANDVAR"'$NOEXPANDVAR//g' file.txt > newfile.txt
In this case sed will replace (remove) pattern one$NOEXPANDVAR , literally.