SED code for removing newline - sed

I am looking for sed command which will transform following line:
>AT1G01020.6 | ARV1 family protein | Chr1:6788-8737 REVERSE LENGTH=944 | 201606
AGACCCGGACTCTAATTGCTCCGTATTCTTCTTCTCTTGAGAGAGAGAGAGAGAGAGAGA
GAGAGAGAGCAATGGCGGCGAGTGAACACAGATGCGTGGGATGTGGTTTTAGGGTAAAGT
CATTGTTCATTCAATACTCTCCGGGGAAATTGCAAGGAAGTAGCAGATGAGTACATCGAG
TGTGAACGCATGATTATTTTCATCGATTTAATCCTTCACAGACCAAAGGTATATAGACAC
into
>AT1G01020.6 | ARV1 family protein | Chr1:6788-8737 REVERSE LENGTH=944 | 201606
AGACCCGGACTCTAATTGCTCCGTATTCTTCTTCTCTTGAGAGAGAGAGAGAGAGAGAGAGAGAGAGAGCAATGGCGGCGAGTGAACACAGATGCGTGGGATGTGGTTTTAGGGTAAAGTCATTGTTCATTCAATACTCTCCGGGGAAATTGCAAGGAAGTAGCAGATGAGTACATCGAGTGTGAACGCATGATTATTTTCATCGATTTAATCCTTCACAGACCAAAGGTATATAGACAC
which means newline after > this character will remain unchanged, while on other cases newlines will be joined.
I have tried with the following line, but it is not working:
sed s/^!>\n$// <in.fasta>out.fasta
I have a 28MB fasta file which I need to transform.

sed is not a particularly good tool for this.
awk '/^>/ { if(prev) printf "\n"; print; next }
{ printf "%s", $0; prev = 1; }
END { if(prev) printf "\n" }' in.fasta >out.fasta

Using awk:
awk '/^>/{print (l?l ORS:"") $0;l="";next}{l=l $0}END{print l}' file
The line is printed if a > or the end of the file is reached, otherwise the line is buffered in the variable l.

Following awk may also help you here. Without using any array or variable's values solution.
awk 'BEGIN{ORS=""} /^>/{if(FNR==1){print $0 RS} else {print RS $0 RS};next}1' Input_file
OR
awk 'BEGIN{ORS=""} /^>/{printf("%s",FNR==1?$0 RS:RS $0 RS);next}1' Input_file

Related

bash while loop failing while using sed

I am facing an issue with sed in a while-loop.using sed. I want to read the 2nd column of file1, compare it with the content of file2, and if the string is matched, i want to replace the matched string of file1 with file2 string.
I tried with the following code, but it is not returning any output.
cat file1 | while read a b; do
sed -i "s/$b/$(grep $b file2)/g" file1 > file3;
done
Example input:
file_1 content:
1 1234
2 8765
file2 content:
12345
34567
87654
Expected output:
1 12345
2 87654
Your script is very inefficient. Using the while-loop you read each line of file1. This is N operations. Per line you process with the while loop, you reproscess the full file1, making it an N*N process. However, in the sed, you grep file2 constantly. If file2 has M lines, this becomes an N*N*M process. This is very inefficient.
On top of that there are some issues:
You updated file1 inplace because you use the -i flag. An inplace update does not provide any output, so file3 will be empty.
You are reading file1 with the while-loop and at the same time you update file1 with sed. I don't know how this will react, but I don't believe it is healthy.
If $b is not in file2 you would, according to your logic, have a line with only a single column. This is not what you expect.
A fix of your script, would be this:
while read -r a b; do
c=$(grep "$b" file2)
[[ "$c" == "" ]] || echo "$a $c"
done < file1 > file3
which is still not efficient, but it is already M*N. The best way is using awk
note: as a novice, always parse your script with http://www.shellcheck.net
note: as a professional, always parse your script with http://www.shellcheck.net
Could you please try following.
awk 'FNR==NR{a[$2]=$1;next} {for(i in a){if(match($0,"^"i)){print a[i],$0;continue}}}' file1 file2
Adding a non-one liner form of solution:
awk '
FNR==NR{
a[$2]=$1
next
}
{
for(i in a){
if(match($0,"^"i)){
print a[i],$0
continue
}
}
}
' Input_file1 Input_file2
Explanation: Adding detailed explanation for above code.
awk ' ##Starting awk code from here.
FNR==NR{ ##Checking condition if FNR==NR then do following.
a[$2]=$1 ##Creating array a whose index is $2 and value is $1.
next ##next will skip all further statements from here.
}
{ ##Statements from here will run for 2nd Input_file only.
for(i in a){ ##Traversing through array a all elements here.
if(match($0,"^"i)){ ##Checking condition if current line matches index of current item from array a then do following.
print a[i],$0 ##Printing array a whose index is i and current line here.
continue ##Again take cursor to for loop.
}
}
}
' Input_file1 Input_file2 ##Mentioning all Input_file names here.

Sed - replace words

I have a problem with replacing string.
|Stm=2|Seq=2|Num=2|Svc=101|MsgSize(514)=514|MsgType=556|SymbolIndex=16631
I want to find occurrence of Svc till | appears and swap place with Stm till | appears.
My attempts went to replacing characters and this is not my goal.
awk -F'|' -v OFS='|'
'{a=b=0;
for(i=1;i<=NF;i++){a=$i~/^Stm=/?i:a;b=$i~/^Svc=/?i:b}
t=$a;$a=$b;$b=t}7' file
outputs:
|Svc=101|Seq=2|Num=2|Stm=2|MsgSize(514)=514|MsgType=556|SymbolIndex=16631
the code exchange the column of Stm.. and Svc.., no matter which one comes first.
If perl solution is okay, assumes only one column matches each for search terms
$ cat ip.txt
|Stm=2|Seq=2|Num=2|Svc=101|MsgSize(514)=514|MsgType=556|SymbolIndex=16631
$ perl -F'\|' -lane '
#i = grep { $F[$_] =~ /Svc|Stm/ } 0..$#F;
$t=$F[$i[0]]; $F[$i[0]]=$F[$i[1]]; $F[$i[1]]=$t;
print join "|", #F;
' ip.txt
|Svc=101|Seq=2|Num=2|Stm=2|MsgSize(514)=514|MsgType=556|SymbolIndex=16631
-F'\|' -lane split input line on |, see also Perl flags -pe, -pi, -p, -w, -d, -i, -t?
#i = grep { $F[$_] =~ /Svc|Stm/ } 0..$#F get index of columns matching Svc and Stm
$t=$F[$i[0]]; $F[$i[0]]=$F[$i[1]]; $F[$i[1]]=$t swap the two columns
Or use ($F[$i[0]], $F[$i[1]]) = ($F[$i[1]], $F[$i[0]]); courtesy How can I swap two Perl variables
print join "|", #F print the modified array
You need to use capture groups and backreferences in a string substition.
The below will swap the 2:
echo '|Stm=2|Seq=2|Num=2|Svc=101|MsgSize(514)=514|MsgType=556|SymbolIndex=16631' | sed 's/\(Stm.*|\)\(.*\)\(Svc.*|\)/\3\2\1/'
As pointed out in the comment from #Kent, this will not work if the strings were not in that order.

Remove newline depending on the format of the next line

I have a special file with this kind of format :
title1
_1 texthere
title2
_2 texthere
I would like all newlines starting with "_" to be placed as a second column to the line before
I tried to do that using sed with this command :
sed 's/_\n/ /g' filename
but it is not giving me what I want to do (doing nothing basically)
Can anyone point me to the right way of doing it ?
Thanks
Try following solution:
In sed the loop is done creating a label (:a), and while not match last line ($!) append next one (N) and return to label a:
:a
$! {
N
b a
}
After this we have the whole file into memory, so do a global substitution for each _ preceded by a newline:
s/\n_/ _/g
p
All together is:
sed -ne ':a ; $! { N ; ba }; s/\n_/ _/g ; p' infile
That yields:
title1 _1 texthere
title2 _2 texthere
If your whole file is like your sample (pairs of lines), then the simplest answer is
paste - - < file
Otherwise
awk '
NR > 1 && /^_/ {printf "%s", OFS}
NR > 1 && !/^_/ {print ""}
{printf "%s", $0}
END {print ""}
' file
This might work for you (GNU sed):
sed ':a;N;s/\n_/ /;ta;P;D' file
This avoids slurping the file into memory.
or:
sed -e ':a' -e 'N' -e 's/\n_/ /' -e 'ta' -e 'P' -e 'D' file
A Perl approach:
perl -00pe 's/\n_/ /g' file
Here, the -00 causes perl to read the file in paragraph mode where a "line" is defined by two consecutive newlines. In your example, it will read the entire file into memory and therefore, a simple global substitution of \n_ with a space will work.
That is not very efficient for very large files though. If your data is too large to fit in memory, use this:
perl -ne 'chomp;
s/^_// ? print "$l " : print "$l\n" if $. > 1;
$l=$_;
END{print "$l\n"}' file
Here, the file is read line by line (-n) and the trailing newline removed from all lines (chomp). At the end of each iteration, the current line is saved as $l ($l=$_). At each line, if the substitution is successful and a _ was removed from the beginning of the line (s/^_//), then the previous line is printed with a space in place of a newline print "$l ". If the substitution failed, the previous line is printed with a newline. The END{} block just prints the final line of the file.

join 2 lines only if field-1 are equals with sed or awk

input file:
$ cat t.txt
id1;value1_1
id1;value1_2
id2;value2_1
id3;value3_1
id4;value4_1
id4;value4_2
id5;value5_1
result would be:
id1;value1_1;id1;value1_2
id3;value3_1
id4;value4_1;id4;value4_2
id5;value5_1
using sed or awk. Please give your opinion.
Here's one way to do it:
awk -F';' 'BEGIN { getline; id=$1; line=$0 } { if ($1 != id) { print line; line = $0; } else { line = line ";" $0; } id=$1; } END { print line; }' t.txt
Explanation:
Set field separator to ;:
-F';'
Start by reading the first line of input (getline), save the first field ($1) as id, and the first line ($0) as line:
BEGIN { getline; id=$1; line=$0 }
For each line of input, check if the first field differs from the stored id:
if ($1 != id)
If it does, then print the saved line and store the new one ($0):
print line; line = $0;
Otherwise, append the new line to the stored line(s):
line = line ";" $0;
And save the new id:
id=$1
At the end, print whatever is left in line:
END { print line; }
I guess in your result example, the id2; line is missing by mistake, right?
anyway, you could try the awk line below:
awk -F';' '{a[$1]=($1 in a)?a[$1]";"$0:$0}END{for(x in a)print a[x]}' yourFile|sort
output would be:
id1;value1_1;id1;value1_2
id2;value2_1
id3;value3_1
id4;value4_1;id4;value4_2
id5;value5_1
This might work for you:
sed -e '1{h;d};H;${x;:a;s/\(\([^;]*;\)\([^\n]*\)\)\n\2/\1;\2/;ta;p};d' t.txt
Explanation:
Slurp file in to hold space (HS) then on end-of-file swap to the HS and using substitution concatenate lines with duplicate keys and print. N.B. lines normally printed are all deleted.
EDIT:
The above solution works (as far as I know) but for large volumes is not very fast (read incredibly slow). This solution is better:
# cat -A /tmp/t.txt
id1;value1_1$
id1;value1_2$
id2;value2_1$
id3;value3_1$
id4;value4_1$
id4;value4_2$
id5;value5_1$
# for x in {1..1000};do cat /tmp/t.txt;done |
> sed ':a;$!N;/^\([^;]*;\).*\n\1/s/\n//;ta;P;D'| sort | uniq
id1;value1_1;id1;value1_2
id2;value2_1
id3;value3_1
id4;value4_1;id4;value4_2
id5;value5_1

awk or sed CSV file manipulation

"a004-1b","North","at006754"
"a004-1c","south","atytgh0"
"a004-1d","east","atrthh"
"a010-1a","midwest","atyu"
"a010-1b","south","rfg67"
I want to print the first column and the second column without any extra character I want eliminate all ("", and the third column) Thanks in advance
awk -F'^"|","|"$' '{print $2,$3}' ./infile.csv
The above script will even handle fields that have embedded double quotes or commas. The only downside (if you can call it that) is that the first field starts at $2
Proof of Concept
$ awk -F'^"|","|"$' '{print $2,$3}' ./infile.csv
a004-1b North
a004-1c south
a010-1a midwest
a010-1b south
You need GNU Awk 4 for this to work:
$ gawk -vFPAT='[^",]+' '{print $1,$2}'
I love this new "field pattern" feature. It's my new hammer and everything is a nail. Read up on it at http://www.gnu.org/software/gawk/manual/html_node/Splitting-By-Content.html
(Written this way it doesn't account for embedded commas or quotes, because the question implies this is not needed.)
If you're using awk for this, why put a Perl tag on it?
In Perl:
#!/usr/bin/env perl
use strict;
use warnings;
use Data::Dumper;
# Make Data::Dumper pretty
$Data::Dumper::Sortkeys = 1;
$Data::Dumper::Indent = 1;
# Set maximum depth for Data::Dumper, zero means unlimited
local $Data::Dumper::Maxdepth = 0;
use Text::CSV;
my $csv = Text::CSV->new();
while( my $row = $csv->getline( \*DATA )){
print 'row: ', Dumper $row;
}
__DATA__
"a004-1b","North","at006754"
"a004-1c","south","atytgh0""a004-1d","east","atrthh"
"a010-1a","midwest","atyu"
"a010-1b","south","rfg67"
awk -F'\"|\,' '{print $2,$5}' sample
Not handling embedded double quotes:
sed -e 's/^"\([^"]*\)","\([^"]*\)".*/\1 \2/'
To handle them:
sed -n -e 's/^"//;s/"$//;s/","/ /;s/","/\n/;P'
The above works even for a 1 or 2 field input.
If you want it "pure" awk or sed, this won't fit the bill, but otherwise it works:
awk -F, '{print $1 " " $2}' | tr -d '"'