How to use m with the ed function in a Bash Script [duplicate] - linux

I just need to move a line up in sed. I can select the line with
sed -i '7s///'
I need to move line 7 up 2 lines so it will be line 5.
I can't find anything on the internet to do this without complicated scripts, I can't find a simple solution of moving a specific line a specific number of times.

seq 10|sed '5{N;h;d};7G'
when up to line 5 append next line(line 6) into pattern space then save them into hold space and delete them from pattern space; up to line 7 then append the hold space content("5\n6") behind the line 7; now, pattern space is "7\n5\n6";finally,sed will print the pattern space at the end of current cycle by default(if no "-n" parameter)

ed is better at this, since it has a "move" command that does exactly what you want. To move line 7 to be the line after line 4, just do 7m4. ed doesn't write the data back by default, so you need to explicitly issue a w command to write the data:
printf '7m4\nw\n' | ed input
Although it is perhaps better to use a more modern tool:
ex -s -c 7m4 -c w -c q input

Related

How to copy multiple lines one under each line separately?

Sorry for the bad english, see this example:
original
a
line01
line02
line03
line04
b
want to become:
a
line01
line01
line02
line02
line03
line03
line04
line04
b
a and b are irrelevant.
I can copy one line and paste, and repeat. Is there any simple solution? like one command?
Using a global command, this could easily be done like this
:g/^/t.
Breakdown
:g start a global command
/^ search for a begin of line (every line matches)
/t. copy the current line
You could also write a vim macro-
With your cursor at line 0, column 0; record a macro, store in register a
qa
Copy the current line; paste it below; move your cursor down to the next line
yypj
Save the Macro
q
Now run the a macro N number of times (it will stop at the bottom of the file regardless)
3#q
For funsies a sed solution:
$ sed 'p' input.txt > output.txt
Using filter, :!, inside of Vim:
:%!sed p
Obligatory awk solution: awk '1;1' input.txt > output.txt.

Sed move a line

I just need to move a line up in sed. I can select the line with
sed -i '7s///'
I need to move line 7 up 2 lines so it will be line 5.
I can't find anything on the internet to do this without complicated scripts, I can't find a simple solution of moving a specific line a specific number of times.
seq 10|sed '5{N;h;d};7G'
when up to line 5 append next line(line 6) into pattern space then save them into hold space and delete them from pattern space; up to line 7 then append the hold space content("5\n6") behind the line 7; now, pattern space is "7\n5\n6";finally,sed will print the pattern space at the end of current cycle by default(if no "-n" parameter)
ed is better at this, since it has a "move" command that does exactly what you want. To move line 7 to be the line after line 4, just do 7m4. ed doesn't write the data back by default, so you need to explicitly issue a w command to write the data:
printf '7m4\nw\n' | ed input
Although it is perhaps better to use a more modern tool:
ex -s -c 7m4 -c w -c q input

Understanding how a Sed script breaks down into individual commands

I'm new to sed, can you tell me what the following does? I can't find a complete regex in the command from below.
sed -e ':a;N;$!ba;s/>[[:space:]]*\n/>\\\n/g' nlTest1.txt > nlTest2.txt
Are we having 3 commands together?
:a;N;$!ba;s
>[[:space:]]*\n
>\\\n/g
Or I'm not intrepreting the command correctly.
The partitioning of the commands is:
:a;N;$!ba, which is a common idiom for reading the entire input file into the pattern space (buffer to operate on) at once, in a loop; it is composed of 3 ;-separated commands:
label :a (defines a script location that can be jumped to)
function N (reads the next line and appends it to the pattern space)
$! ba, which branches (b) to label a, if the input line is not (!) the last ($) one.
s/>[[:space:]]*\n/>\\\n/g is a regular s function call in the form s/<regex>/<substitution-string>/; here, all occurrences of a > followed by any run of whitespace followed by a newline are replaced with just >\ and a newline.

How do I write a sed script to grep information from a text file

I'm trying to do my homework that is restricted to only using sed to filter an input file to a certain format of output. Here is the input file (named stocks):
Symbol;Name;Volume
================================================
BAC;Bank of America Corporation Com;238,059,612
CSCO;Cisco Systems, Inc.;28,159,455
INTC;Intel Corporation;22,501,784
MSFT;Microsoft Corporation;23,363,118
VZ;Verizon Communications Inc. Com;5,744,385
KO;Coca-Cola Company (The) Common;3,752,569
MMM;3M Company Common Stock;1,660,453
================================================
And the output needs to be:
BAC, CSCO, INTC, MSFT, VZ, KO, MMM
I did come up with a solution, but it's not efficient. Here is my sed script (named try.sed):
/.*;.*;[0-9].*/ { N
N
N
N
N
N
s/\(.*\);.*;.*\n\(.*\);.*;.*\n\(.*\);.*;.*\n\(.*\);.*;.*\n\(.*\);.*;.*\n\(.*\);.*;.*\n\(.*\);.*;.*/\1, \2, \3, \4, \5, \6, \7/gp
}
The command that I run on shell is:
$ sed -nf try.sed stocks
My question is, is there a better way of using sed to get the same result? The script I wrote only works with 7 lines of data. If the data is longer, I need to re-modify my script. I'm not sure how I can make it any better, so I'm here asking for help!
Thanks for any recommendations.
One more way using sed:
sed -ne '/^====/,/^====/ { /;/ { s/;.*$// ; H } }; $ { g ; s/\n// ; s/\n/, /g ; p }' stocks
Output:
BAC, CSCO, INTC, MSFT, VZ, KO, MMM
Explanation:
-ne # Process each input line without printing and execute next commands...
/^====/,/^====/ # For all lines between these...
{
/;/ # If line has a semicolon...
{
s/;.*$// # Remove characters from first semicolon until end of line.
H # Append content to 'hold space'.
}
};
$ # In last input line...
{
g # Copy content of 'hold space' to 'pattern space' to work with it.
s/\n// # Remove first newline character.
s/\n/, /g # substitute the rest with output separator, comma in this case.
p # Print to output.
Edit: I've edited my algorithm, since I had neglected to consider the header and footer (I thought they were just for our benefit).
sed, by its design, accesses every line of an input file, and then performs expressions on ones that match some specification (or none). If you're tailoring your script to a certain number of lines, you're definitely doing something wrong! I won't write you a script since this is homework, but the general idea for one way to go about it is to write a script that does the following. Think of the ordering as the order things should be in a script.
Skip the first three lines using d, which deletes the pattern space and immediately moves on to the next line.
For each line that isn't a blank line, do the following steps. (This would all be in a single set of curly braces.)
Replace everything after and including the first semicolon (;) with a comma-and-space (", ") using the s (substitute) command.
Append the current pattern space into the hold buffer (look at H).
Delete the pattern space and move on to the next line, like in step 1.
For each line that gets to this point in the script (should be the first blank line), retrieve the contents of the hold space into the pattern space. (This would be after the curly braces above.)
Substitute all newlines in the pattern space with nothing.
Next, substitute the last comma-and-space in the pattern space with nothing.
Finally, quit the program so you don't process any more lines. My script worked without this, but I'm not 100% sure why.
That being said, that's just one way to go about it. sed often offers varying ways of varying complexity to accomplish a task. A solution I wrote with this method is 10 lines long.
As a note, I don't bother suppressing printing (with -n) or manually printing (with p); each line is printed by default. My script runs like this:
$ sed -f companies.sed companies
BAC, CSCO, INTC, MSFT, VZ, KO, MMM
This sed command should produce your required output:
sed -rn '/[0-9]+$/{s/^([^;]*).*$/\1/p;}' file.txt
OR on Mac:
sed -En '/[0-9]+$/{s/^([^;]*).*$/\1/p;}' file.txt
This might work for you:
sed '1d;/;/{s/;.*//;H};${g;s/.//;s/\n/, /g;q};d' stocks
We don't want the headings so let's delete them. 1d
All data items are delimited by ;'s so let's concentrate on those lines. /;/
Of the things above delete everything from the first ; to the end of line and then stuff it away in the the hold space (HS) {s/;.*//;H}
When you get to the last line, overwrite it with the HS using the g command, delete the first newline (generated by the H command), replace all subsequent newlines with a comma and a space and print out what's left. ${g;s/.//;s/\n/, /g;q}
Delete everything else d
Here's a terminal session showing the incremental refinement of building a sed command:
cat <<! >stock # paste the file into a here doc and pass it on to a file
> Symbol;Name;Volume
> ================================================
>
> BAC;Bank of America Corporation Com;238,059,612
> CSCO;Cisco Systems, Inc.;28,159,455
> INTC;Intel Corporation;22,501,784
> MSFT;Microsoft Corporation;23,363,118
> VZ;Verizon Communications Inc. Com;5,744,385
> KO;Coca-Cola Company (The) Common;3,752,569
> MMM;3M Company Common Stock;1,660,453
>
> ================================================
> !
sed '1d;/;/!d' stock # delete headings and everything but data lines
BAC;Bank of America Corporation Com;238,059,612
CSCO;Cisco Systems, Inc.;28,159,455
INTC;Intel Corporation;22,501,784
MSFT;Microsoft Corporation;23,363,118
VZ;Verizon Communications Inc. Com;5,744,385
KO;Coca-Cola Company (The) Common;3,752,569
MMM;3M Company Common Stock;1,660,453
sed '1d;/;/{s/;.*//p};d' stock # delete all non essential data
BAC
CSCO
INTC
MSFT
VZ
KO
MMM
sed '1d;/;/{s/;.*//;H};${g;l};d' stock # use the l command to see what's really there!
\nBAC\nCSCO\nINTC\nMSFT\nVZ\nKO\nMMM$
sed '1d;/;/{s/;.*//;H};${g;s/.//;s/\n/, /g;l};d' stock # refine refine
BAC, CSCO, INTC, MSFT, VZ, KO, MMM$
sed '1d;/;/{s/;.*//;H};${g;s/.//;s/\n/, /g;q};d' stock # all done!
BAC, CSCO, INTC, MSFT, VZ, KO, MMM

How can I replace a specific line by line number in a text file?

I have a 2GB text file on my linux box that I'm trying to import into my database.
The problem I'm having is that the script that is processing this rdf file is choking on one line:
mismatched tag at line 25462599, column 2, byte 1455502679:
<link r:resource="http://www.epuron.de/"/>
<link r:resource="http://www.oekoworld.com/"/>
</Topic>
=^
I want to replace the </Topic> with </Line>. I can't do a search/replace on all lines but I do have the line number so I'm hoping theres some easy way to just replace that one line with the new text.
Any ideas/suggestions?
sed -i yourfile.xml -e '25462599s!</Topic>!</Line>!'
sed -i '25462599 s|</Topic>|</Line>|' nameoffile.txt
The tool for editing text files in Unix, is called ed (as opposed to sed, which as the name implies is a stream editor).
ed was once intended as an interactive editor, but it can also easily scripted. The way ed works, is that all commands take an address parameter. The way to address a specific line is just the line number, and the way to change the addressed line(s) is the s command, which takes the same regexp that sed would. So, to change the 42nd line, you would write something like 42s/old/new/.
Here's the entire command:
FILENAME=/path/to/whereever
LINENUMBER=25462599
ed -- "${FILENAME}" <<-HERE
${LINENUMBER}s!</Topic>!</Line>!
w
q
HERE
The advantage of this is that ed is standardized, while the -i flag to sed is a proprietary GNU extension that is not available on a lot of systems.
Use "head" to get the first 25462598 lines and use "tail" to get the remaining lines (starting at 25462601). Though... for a 2GB file this will likely take a while.
Also are you sure the problem is just with that line and not somewhere previous (ie. the error looks like an XML parse error which might mean the actual problem is someplace else).
My shell script:
#!/bin/bash
awk -v line=$1 -v new_content="$2" '{
if (NR == line) {
print new_content;
} else {
print $0;
}
}' $3
Arguments:
first: line number you want change
second: text you want instead original line contents
third: file name
This script prints output to stdout then you need to redirect. Example:
./script.sh 5 "New fifth line text!" file.txt
You can improve it, for example, by taking care that all your arguments has expected values.

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