I have a file filled with two line couplets, a header line that starts with // and ends with the line number surrounded by |, followed by a line of text that is variable in length. Here's an example, where ... indicates that the file continues with sequential line numbers for many lines.
// * * - - - * |1|
textextextextextextextext
// *- *-* * |2|
textextextextextextextexttextextextext
...
// * - * -* |41232|
textextextextextextext
I would like to find the line number, then replace the header line with >linenumber. This example file would be:
>1
textextextextextextextext
>2
textextextextextextextexttextextextext
...
>41232
textextextextextextext
I know this probably involves /s and sed or awk with a backreference, but I'm just can't seem to make it work.
A sed one-liner:
sed 's%^//.*|\([0-9]*\)|$%>\1%' file
Yes, sed is a good tool to do it:
sed -E '\%^//.*\|[[:digit:]]+\|% s/.*\|([[:digit:]]+)\|/>\1/'
Explanation:
\%^//.*\|[[:digit:]]+\|% This is an address, i.e. the following s/// command will only run on matching lines. It matches // at the start of a line, and somewhere later there must be a number between vertical bars.
The substitution replaces the whole line with the captured number.
Using any awk:
$ awk -F'|' 'NF>1{$0=">" $2} 1' file
>1
textextextextextextextext
>2
textextextextextextextexttextextextext
...
>41232
textextextextextextext
The above assumes that text never includes |s.
Related
I got a text like this:
TOKEN = decrypt_aes(
"189272123124aqephkiz3")
And I want to change it into:
TOKEN = "189272123124aqephkiz3"
How can I make this?
I can do this when its in a single line with following command:enter code here`
sed -i "s/decrypt_aes(\(.*\))/\1/g"
But I don`t no how to do when its in multi line
If your file contains only the two lines you showed, then this might help with GNU sed:
sed -i 'N; s/decrypt_aes(\n *//; s/)//' file
From man sed:
N: Append the next line of input into the pattern space.
You can use
sed -i '/.*decrypt_aes($/{N;s/^\([^=]*=\).*\(".*"\))$/\1 \2/}' file
Details:
/.*decrypt_aes($/ - matches a line that ends with decrypt_aes( substring, and if it matches, the block that follows is executed
N - append a newline and the next line to the pattern space
s/^\([^=]*=\).*\(".*"\))$/\1 \2/ - replaces
^\([^=]*=\).*\(".*"\))$ - start of string in the pattern space (^), any zero or more chars other than = and then a = are captured into Group 1 (\1), then any text (.*), then a "..." substring (captured into Group 2 (\2)) and then a ) at the end of string
\1 \2 is the replacement pattern, which is Group 1 value + space + Group 2 value.
See the online demo:
#!/bin/bash
s='TOKEN = decrypt_aes(
"189272123124aqephkiz3")'
sed '/.*decrypt_aes($/{N;s/^\([^=]*=\).*\(".*"\))$/\1 \2/}' <<< "$s"
Output:
TOKEN = "189272123124aqephkiz3"
This might work for you (GNU sed):
sed 'N;s/decrypt_aes.*\(".*"\).*/\1/;P;D' file
Append the following line and if the combined lines matches decrpty_aes followed by "...", replace the match by the string "...".
N.B. If no match is found, each line will be printed as is.
I have been tinkering with this for a while but can't quite figure it out. A sample line within the file looks like this:
"...~236 characters of data...Y YYY. Y...many more characters of data"
How would I use sed or awk to replace spaces with a B character only between positions 236 and 246? In that example string it starts at character 29 and ends at character 39 within the string. I would want to preserve all the text preceding and following the target chunk of data within the line.
For clarification based on the comments, it should be applied to all lines in the file and expected output would be:
"...~236 characters of data...YBBYYY.BBY...many more characters of data"
With GNU awk:
$ awk -v FIELDWIDTHS='29 10 *' -v OFS= '{gsub(/ /, "B", $2)} 1' ip.txt
...~236 characters of data...YBBYYY.BBY...many more characters of data
FIELDWIDTHS='29 10 *' means 29 characters for first field, next 10 characters for second field and the rest for third field. OFS is set to empty, otherwise you'll get space added between the fields.
With perl:
$ perl -pe 's/^.{29}\K.{10}/$&=~tr| |B|r/e' ip.txt
...~236 characters of data...YBBYYY.BBY...many more characters of data
^.{29}\K match and ignore first 29 characters
.{10} match 10 characters
e flag to allow Perl code instead of string in replacement section
$&=~tr| |B|r convert space to B for the matched portion
Use this Perl one-liner with substr and tr. Note that this uses the fact that you can assign to substr, which changes the original string:
perl -lpe 'BEGIN { $from = 29; $to = 39; } (substr $_, ( $from - 1 ), ( $to - $from + 1 ) ) =~ tr/ /B/;' in_file > out_file
To change the file in-place, use:
perl -i.bak -lpe 'BEGIN { $from = 29; $to = 39; } (substr $_, ( $from - 1 ), ( $to - $from + 1 ) ) =~ tr/ /B/;' in_file
The Perl one-liner uses these command line flags:
-e : Tells Perl to look for code in-line, instead of in a file.
-p : Loop over the input one line at a time, assigning it to $_ by default. Add print $_ after each loop iteration.
-l : Strip the input line separator ("\n" on *NIX by default) before executing the code in-line, and append it when printing.
-i.bak : Edit input files in-place (overwrite the input file). Before overwriting, save a backup copy of the original file by appending to its name the extension .bak.
I would use GNU AWK following way, for simplicity sake say we have file.txt content
S o m e s t r i n g
and want to change spaces from 5 (inclusive) to 10 (inclusive) position then
awk 'BEGIN{FPAT=".";OFS=""}{for(i=5;i<=10;i+=1)$i=($i==" "?"B":$i);print}' file.txt
output is
S o mBeBsBt r i n g
Explanation: I set field pattern (FPAT) to any single character and output field seperator (OFS) to empty string, thus every field is populated by single characters and I do not get superfluous space when print-ing. I use for loop to access desired fields and for every one I check if it is space, if it is I assign B here otherwise I assign original value, finally I print whole changed line.
Using GNU awk:
awk -v strt=29 -v end=39 '{ ram=substr($0,strt,(end-strt));gsub(" ","B",ram);print substr($0,1,(strt-1)) ram substr($0,(end)) }' file
Explanation:
awk -v strt=29 -v end=39 '{ # Pass the start and end character positions as strt and end respectively
ram=substr($0,strt,(end-strt)); # Extract the 29th to the 39th characters of the line and read into variable ram
gsub(" ","B",ram); # Replace spaces with B in ram
print substr($0,1,(strt-1)) ram substr($0,(end)) # Rebuild the line incorporating raw and printing the result
}'file
This is certainly a suitable task for perl, and saddens me that my perl has become so rusty that this is the best I can come up with at the moment:
perl -e 'local $/=\1;while(<>) { s/ /B/ if $. >= 236 && $. <= 246; print }' input;
Another awk but using FS="":
$ awk 'BEGIN{FS=OFS=""}{for(i=29;i<=39;i++)sub(/ /,"B",$i)}1' file
Output:
"...~236 characters of data...YBBYYY.BBY...many more characters of data"
Explained:
$ awk ' # yes awk yes
BEGIN {
FS=OFS="" # set empty field delimiters
}
{
for(i=29;i<=39;i++) # between desired indexes
sub(/ /,"B",$i) # replace space with B
# if($i==" ") # couldve taken this route, too
# $i="B"
}1' file # implicit output
With sed :
sed '
H
s/\(.\{236\}\)\(.\{11\}\).*/\2/
s/ /B/g
H
g
s/\n//g
s/\(.\{236\}\)\(.\{11\}\)\(.*\)\(.\{11\}\)/\1\4\3/
x
s/.*//
x' infile
When you have an input string without \r, you can use:
sed -r 's/(.{236})(.{10})(.*)/\1\r\2\r\3/;:a;s/(\r.*) (.*\r)/\1B\2/;ta;s/\r//g' input
Explanation:
First put \r around the area that you want to change.
Next introduce a label to jump back to.
Next replace a space between 2 markers.
Repeat until all spaces are replaced.
Remove the markers.
In your case, where the length doesn't change, you can do without the markers.
Replace a space after 236..245 characters and try again when it succeeds.
sed -r ':a; s/^(.{236})([^ ]{0,9}) /\1\2B/;ta' input
This might work for you (GNU sed):
sed -E 's/./&\n/245;s//\n&/236/;h;y/ /B/;H;g;s/\n.*\n(.*)\n.*\n(.*)\n.*/\2\1/' file
Divide the problem into 2 lines, one with spaces and one with B's where there were spaces.
Then using pattern matching make a composite line from the two lines.
N.B. The newline can be used as a delimiter as it is guaranteed not to be in seds pattern space.
UPDATED:
Using sed, how can I insert (NOT SUBSTITUTE) a new line on only the first match of keyword for each file.
Currently I have the following but this inserts for every line containing Matched Keyword and I want it to only insert the New Inserted Line for only the first match found in the file:
sed -ie '/Matched Keyword/ i\New Inserted Line' *.*
For example:
Myfile.txt:
Line 1
Line 2
Line 3
This line contains the Matched Keyword and other stuff
Line 4
This line contains the Matched Keyword and other stuff
Line 6
changed to:
Line 1
Line 2
Line 3
New Inserted Line
This line contains the Matched Keyword and other stuff
Line 4
This line contains the Matched Keyword and other stuff
Line 6
You can sort of do this in GNU sed:
sed '0,/Matched Keyword/s//New Inserted Line\n&/'
But it's not portable. Since portability is good, here it is in awk:
awk '/Matched Keyword/ && !x {print "Text line to insert"; x=1} 1' inputFile
Or, if you want to pass a variable to print:
awk -v "var=$var" '/Matched Keyword/ && !x {print var; x=1} 1' inputFile
These both insert the text line before the first occurrence of the keyword, on a line by itself, per your example.
Remember that with both sed and awk, the matched keyword is a regular expression, not just a keyword.
UPDATE:
Since this question is also tagged bash, here's a simple solution that is pure bash and doesn't required sed:
#!/bin/bash
n=0
while read line; do
if [[ "$line" =~ 'Matched Keyword' && $n = 0 ]]; then
echo "New Inserted Line"
n=1
fi
echo "$line"
done
As it stands, this as a pipe. You can easily wrap it in something that acts on files instead.
If you want one with sed*:
sed '0,/Matched Keyword/s//Matched Keyword\nNew Inserted Line/' myfile.txt
*only works with GNU sed
This might work for you:
sed -i -e '/Matched Keyword/{i\New Inserted Line' -e ':a;n;ba}' file
You're nearly there! Just create a loop to read from the Matched Keyword to the end of the file.
After inserting a line, the remainder of the file can be printed out by:
Introducing a loop place holder :a (here a is an arbitrary name).
Print the current line and fetch the next into the pattern space with the ncommand.
Redirect control back using the ba command which is essentially a goto to the a place holder. The end-of-file condition is naturally taken care of by the n command which terminates any further sed commands if it tries to read passed the end-of-file.
With a little help from bash, a true one liner can be achieved:
sed $'/Matched Keyword/{iNew Inserted Line\n:a;n;ba}' file
Alternative:
sed 'x;/./{x;b};x;/Matched Keyword/h;//iNew Inserted Line' file
This uses the Matched Keyword as a flag in the hold space and once it has been set any processing is curtailed by bailing out immediately.
If you want to append a line after first match only, use AWK instead of SED as below
awk '{print} /Matched Keyword/ && !n {print "New Inserted Line"; n++}' myfile.txt
Output:
Line 1
Line 2
Line 3
This line contains the Matched Keyword and other stuff
New Inserted Line
Line 4
This line contains the Matched Keyword and other stuff
Line 6
I have two files. One file contains a pattern that I want to match in a second file. I want to use that pattern to print between that pattern (included) up to a specified character (not included) and then concatenate into a single output file.
For instance,
File_1:
a
c
d
and File_2:
>a
MEEL
>b
MLPK
>c
MEHL
>d
MLWL
>e
MTNH
I have been using variations of this loop:
while read $id;
do
sed -n "/>$id/,/>/{//!p;}" File_2;
done < File_1
hoping to obtain something like the following output:
>a
MEEL
>c
MEHL
>d
MLWL
But have had no such luck. I have played around with grep/fgrep awk and sed and between the three cannot seem to get the right (or any output). Would someone kindly point me in the right direction?
Try:
$ awk -F'>' 'FNR==NR{a[$1]; next} NF==2{f=$2 in a} f' file1 file2
>a
MEEL
>c
MEHL
>d
MLWL
How it works
-F'>'
This sets the field separator to >.
FNR==NR{a[$1]; next}
While reading in the first file, this creates a key in array a for every line in file file.
NF==2{f=$2 in a}
For every line in file 2 that has two fields, this sets variable f to true if the second field is a key in a or false if it is not.
f
If f is true, print the line.
A plain (GNU) sed solution. Files are read only once. It is assumed that characters in File_1 needn't to be quoted in sed expression.
pat=$(sed ':a; $!{N;ba;}; y/\n/|/' File_1)
sed -E -n ":a; /^>($pat)/{:b; p; n; /^>/ba; bb}" File_2
Explanation:
The first call to sed generates a regular expression to be used in the second call to sed and stores it in the variable pat. The aim is to avoid reading repeatedly the entire File_2 for each line of File_1. It just "slurps" the File_1 and replaces new-line characters with | characters. So the sample File_1 becomes a string with the value a|c|d. The regular expression a|c|d matches if at least one of the alternatives (a, b, c for this example) matches (this is a GNU sed extension).
The second sed expression, ":a; /^>($pat)/{:b; p; n; /^>/ba; bb}", could be converted to pseudo code like this:
begin:
read next line (from File_2) or quit on end-of-file
label_a:
if line begins with `>` followed by one of the alternatives in `pat` then
label_b:
print the line
read next line (from File_2) or quit on end-of-file
if line begins with `>` goto label_a else goto label_b
else goto begin
Let me try to explain why your approach does not work well:
You need to say while read id instead of while read $id.
The sed command />$id/,/>/{//!p;} will exclude the lines which start
with >.
Then you might want to say something like:
while read id; do
sed -n "/^>$id/{N;p}" File_2
done < File_1
Output:
>a
MEEL
>c
MEHL
>d
MLWL
But the code above is inefficient because it reads File_2 as many times as the count of the id's in File_1.
Please try the elegant solution by John1024 instead.
If ed is available, and since the shell is involve.
#!/usr/bin/env bash
mapfile -t to_match < file1.txt
ed -s file2.txt <<-EOF
g/\(^>[${to_match[*]}]\)/;/^>/-1p
q
EOF
It will only run ed once and not every line that has the pattern, that matches from file1. Like say if you have a to z from file1,ed will not run 26 times.
Requires bash4+ because of mapfile.
How it works
mapfile -t to_match < file1.txt
Saves the entry/value from file1 in an array named to_match
ed -s file2.txt point ed to file2 with the -s flag which means don't print info about the file, same info you get with wc file
<<-EOF A here document, shell syntax.
g/\(^>[${to_match[*]}]\)/;/^>/-1p
g means search the whole file aka global.
( ) capture group, it needs escaping because ed only supports BRE, basic regular expression.
^> If line starts with a > the ^ is an anchor which means the start.
[ ] is a bracket expression match whatever is inside of it, in this case the value of the array "${to_match[*]}"
; Include the next address/pattern
/^>/ Match a leading >
-1 go back one line after the pattern match.
p print whatever was matched by the pattern.
q quit ed
I'm trying to delete two lines either side of a pattern match from a file full of transactions. Ie. find the match then delete two lines before it, then delete two lines after it and then delete the match. The write this back to the original file.
So the input data is
D28/10/2011
T-3.48
PINITIAL BALANCE
M
^
and my pattern is
sed -i '/PINITIAL BALANCE/,+2d' test.txt
However this is only deleting two lines after the pattern match and then deleting the pattern match. I can't work out any logical way to delete all 5 lines of data from the original file using sed.
an awk one-liner may do the job:
awk '/PINITIAL BALANCE/{for(x=NR-2;x<=NR+2;x++)d[x];}{a[NR]=$0}END{for(i=1;i<=NR;i++)if(!(i in d))print a[i]}' file
test:
kent$ cat file
######
foo
D28/10/2011
T-3.48
PINITIAL BALANCE
M
x
bar
######
this line will be kept
here
comes
PINITIAL BALANCE
again
blah
this line will be kept too
########
kent$ awk '/PINITIAL BALANCE/{for(x=NR-2;x<=NR+2;x++)d[x];}{a[NR]=$0}END{for(i=1;i<=NR;i++)if(!(i in d))print a[i]}' file
######
foo
bar
######
this line will be kept
this line will be kept too
########
add some explanation
awk '/PINITIAL BALANCE/{for(x=NR-2;x<=NR+2;x++)d[x];} #if match found, add the line and +- 2 lines' line number in an array "d"
{a[NR]=$0} # save all lines in an array with line number as index
END{for(i=1;i<=NR;i++)if(!(i in d))print a[i]}' #finally print only those index not in array "d"
file # your input file
sed will do it:
sed '/\n/!N;/\n.*\n/!N;/\n.*\n.*PINITIAL BALANCE/{$d;N;N;d};P;D'
It works this way:
if sed has only one string in pattern space it joins another one
if there are only two it joins the third one
if it does natch to pattern LINE + LINE + LINE with BALANCE it joins two following strings, deletes them and goes at the beginning
if not, it prints the first string from pattern and deletes it and goes at the beginning without swiping the pattern space
To prevent the appearance of pattern on the first string you should modify the script:
sed '1{/PINITIAL BALANCE/{N;N;d}};/\n/!N;/\n.*\n/!N;/\n.*\n.*PINITIAL BALANCE/{$d;N;N;d};P;D'
However, it fails in case you have another PINITIAL BALANCE in string which are going to be deleted. However, other solutions fails too =)
For such a task, I would probably reach for a more advanced tool like Perl:
perl -ne 'push #x, $_;
if (#x > 4) {
if ($x[2] =~ /PINITIAL BALANCE/) { undef #x }
else { print shift #x }
}
END { print #x }' input-file > output-file
This will remove 5 lines from the input file. These lines will be the 2 lines before the match, the matched line, and the two lines afterwards. You can change the total number of lines being removed modifying #x > 4 (this removes 5 lines) and the line being matched modifying $x[2] (this makes the match on the third line to be removed and so removes the two lines before the match).
A more simple and easy to understand solution might be:
awk '/PINITIAL BALANCE/ {print NR-2 "," NR+2 "d"}' input_filename \
| sed -f - input_filename > output_filename
awk is used to make a sed-script that deletes the lines in question and the result is written on the output_filename.
This uses two processes which might be less efficient than the other answers.
This might work for you (GNU sed):
sed ':a;$q;N;s/\n/&/2;Ta;/\nPINITIAL BALANCE$/!{P;D};$q;N;$q;N;d' file
save this code into a file grep.sed
H
s:.*::
x
s:^\n::
:r
/PINITIAL BALANCE/ {
N
N
d
}
/.*\n.*\n/ {
P
D
}
x
d
and run a command like this:
`sed -i -f grep.sed FILE`
You can use it so either:
sed -i 'H;s:.*::;x;s:^\n::;:r;/PINITIAL BALANCE/{N;N;d;};/.*\n.*\n/{P;D;};x;d' FILE