I have the following string that I want to extract name and id from and store them in a variable. This is just an example, the list can be longer but they are separated the same way.
[["freepbx","NEWUPDATES","There are 6 modules available for online upgrades"],["cidlookup","noauth","OpenCNAM Requires Authentication"]]
The id's in the string is freepbx and cidlookup, the names are NEWUPDATES and noauth.
I'd like them to come out like:
freepbx NEWUPDATES
cidlookup noauth
I'm running a program from command line that needs it's input this way.
Any help is greatly appreciated!
This is one way to do it:
echo '[["freepbx","NEWUPDATES","There are 6 modules available for online upgrades"],["cidlookup","noauth","OpenCNAM Requires Authentication"]]' | sed -e 's/\],\[/\n/g' -e 's/\(\[\[\)*"//g' | awk -F ',' '{print $1, $2}'
freepbx NEWUPDATES
cidlookup noauth
Explanation:
The sed command s/\],\[/\n/g will replace all ], [ which separate each record with a new line(\n) character. This will allow you to treat each line as a separate record which makes all other tools much easier:)
The second sed command s/\(\[\[\)*"//g will remove the quotes and the initial [[ at the start of the first record. This cleans up things from your data leaving only the , between your fields.
Finally, awk command -F ',' '{print $1, $2}', the -F tells awk to use the , as field separator (instead of space) and $1 and $2 to print the first and second fields.
awk to the rescue!
$ awk -F'"' -v RS="\\\],\\\[" '{print $2,$4}' file
freepbx NEWUPDATES
cidlookup noauth
If jq is available:
jq -r '.[] | "\(.[0]) \(.[1])"'
Pipe .[] ( all elements in the array) output to print only 0th and 1st element "\(.[0]) \(.[1])"as in desired output.
Related
Without using sed or awk, only cut, how do I get the last field when the number of fields are unknown or change with every line?
You could try something like this:
echo 'maps.google.com' | rev | cut -d'.' -f 1 | rev
Explanation
rev reverses "maps.google.com" to be moc.elgoog.spam
cut uses dot (ie '.') as the delimiter, and chooses the first field, which is moc
lastly, we reverse it again to get com
Use a parameter expansion. This is much more efficient than any kind of external command, cut (or grep) included.
data=foo,bar,baz,qux
last=${data##*,}
See BashFAQ #100 for an introduction to native string manipulation in bash.
It is not possible using just cut. Here is a way using grep:
grep -o '[^,]*$'
Replace the comma for other delimiters.
Explanation:
-o (--only-matching) only outputs the part of the input that matches the pattern (the default is to print the entire line if it contains a match).
[^,] is a character class that matches any character other than a comma.
* matches the preceding pattern zero or more time, so [^,]* matches zero or more non‑comma characters.
$ matches the end of the string.
Putting this together, the pattern matches zero or more non-comma characters at the end of the string.
When there are multiple possible matches, grep prefers the one that starts earliest. So the entire last field will be matched.
Full example:
If we have a file called data.csv containing
one,two,three
foo,bar
then grep -o '[^,]*$' < data.csv will output
three
bar
Without awk ?...
But it's so simple with awk:
echo 'maps.google.com' | awk -F. '{print $NF}'
AWK is a way more powerful tool to have in your pocket.
-F if for field separator
NF is the number of fields (also stands for the index of the last)
There are multiple ways. You may use this too.
echo "Your string here"| tr ' ' '\n' | tail -n1
> here
Obviously, the blank space input for tr command should be replaced with the delimiter you need.
This is the only solution possible for using nothing but cut:
echo "s.t.r.i.n.g." | cut -d'.' -f2-
[repeat_following_part_forever_or_until_out_of_memory:] | cut -d'.' -f2-
Using this solution, the number of fields can indeed be unknown and vary from time to time. However as line length must not exceed LINE_MAX characters or fields, including the new-line character, then an arbitrary number of fields can never be part as a real condition of this solution.
Yes, a very silly solution but the only one that meets the criterias I think.
If your input string doesn't contain forward slashes then you can use basename and a subshell:
$ basename "$(echo 'maps.google.com' | tr '.' '/')"
This doesn't use sed or awk but it also doesn't use cut either, so I'm not quite sure if it qualifies as an answer to the question as its worded.
This doesn't work well if processing input strings that can contain forward slashes. A workaround for that situation would be to replace forward slash with some other character that you know isn't part of a valid input string. For example, the pipe (|) character is also not allowed in filenames, so this would work:
$ basename "$(echo 'maps.google.com/some/url/things' | tr '/' '|' | tr '.' '/')" | tr '|' '/'
the following implements A friend's suggestion
#!/bin/bash
rcut(){
nu="$( echo $1 | cut -d"$DELIM" -f 2- )"
if [ "$nu" != "$1" ]
then
rcut "$nu"
else
echo "$nu"
fi
}
$ export DELIM=.
$ rcut a.b.c.d
d
An alternative using perl would be:
perl -pe 's/(.*) (.*)$/$2/' file
where you may change \t for whichever the delimiter of file is
It is better to use awk while working with tabular data. You don't have to master on command. If it can be achieved by awk, why not use that? I suggest you do not waste your precious time, and use a handful of commands to get the job done.
Example:
# $NF refers to the last column in awk
ll | awk '{print $NF}'
If you have a file named filelist.txt that is a list paths such as the following:
c:/dir1/dir2/file1.h
c:/dir1/dir2/dir3/file2.h
then you can do this:
rev filelist.txt | cut -d"/" -f1 | rev
Adding an approach to this old question just for the fun of it:
$ cat input.file # file containing input that needs to be processed
a;b;c;d;e
1;2;3;4;5
no delimiter here
124;adsf;15454
foo;bar;is;null;info
$ cat tmp.sh # showing off the script to do the job
#!/bin/bash
delim=';'
while read -r line; do
while [[ "$line" =~ "$delim" ]]; do
line=$(cut -d"$delim" -f 2- <<<"$line")
done
echo "$line"
done < input.file
$ ./tmp.sh # output of above script/processed input file
e
5
no delimiter here
15454
info
Besides bash, only cut is used.
Well, and echo, I guess.
choose -1
choose supports negative indexing (the syntax is similar to Python's slices).
I realized if we just ensure a trailing delimiter exists, it works. So in my case I have comma and whitespace delimiters. I add a space at the end;
$ ans="a, b"
$ ans+=" "; echo ${ans} | tr ',' ' ' | tr -s ' ' | cut -d' ' -f2
b
I need to grep some pattern and further i need to print some output within that. Currently I am using the below command which is working fine. But I like to eliminate using multiple pipe and want to use single awk command to achieve the same output. Is there a way to do it using awk?
root#Server1 # cat file
Jenny:Mon,Tue,Wed:Morning
David:Thu,Fri,Sat:Evening
root#Server1 # awk '/Jenny/ {print $0}' file | awk -F ":" '{ print $2 }' | awk -F "," '{ print $1 }'
Mon
I want to get this output using single awk command. Any help?
You can try something like:
awk -F: '/Jenny/ {split($2,a,","); print a[1]}' file
Try this
awk -F'[:,]+' '/Jenny/{print $2}' file.txt
It is using muliple -F value inside the [ ]
The + means one or more since it is treated as a regex.
For this particular job, I find grep to be slightly more robust.
Unless your company has a policy not to hire people named Eve.
(Try it out if you don't understand.)
grep -oP '^[^:]*Jenny[^:]*:\K[^,:]+' file
Or to do a whole-word match:
grep -oP '^[^:]*\bJenny\b[^:]*:\K[^,:]+' file
Or when you are confident that "Jenny" is the full name:
grep -oP '^Jenny:\K[^,:]+' file
Output:
Mon
Explanation:
The stuff up until \K speaks for itself: it selects the line(s) with the desired name.
[^,:]+ captures the day of week (in this case Mon).
\K cuts off everything preceding Mon.
-o cuts off anything following Mon.
I have CSV columns that I'm working with:
info,example-string,super-example-string,otherinfo
I would like to get:
example-string super example string
Right now, I'm running the following command:
awk -F ',' '{print $3}' | sed "s/-//g"
But, then I have to paste the lines together to combine $2 and $3.
Is there anyway to do something like this?
awk -F ',' '{print $2" "$3}' | sed "s/-//g"
Except, where the sed command is only performed on $3 and $2 stays in place? I'm just concerned later on if the lines don't match up, the data could be misaligned.
Please note: I need to keep the pipe for the SED command. I just used a simple example but I end up running a lot of commands after that as well.
Try:
$ awk -F, '{gsub(/-/," ",$3); print $2,$3}' file
example-string super example string
How it works
-F,
This tells awk to use a comma as the field separator.
gsub(/-/," ",$3)
This replaces all - in field 3 with spaces.
print $2,$3
This prints fields 2 and 3.
Examples using pipelines
$ echo 'info,example-string,super-example-string,otherinfo' | awk -F, '{gsub(/-/," ",$3); print $2,$3}'
example-string super example string
In a pipeline with sed:
$ echo 'info,example-string,super-example-string,otherinfo' | awk -F, '{gsub(/-/," ",$3); print $2,$3}' | sed 's/string/String/g'
example-String super example String
Though best solution will be either use a single sed or use single awk. Since you have requested to use awk and sed solution so providing this. Also considering your actual data will be same as shown sample Input_file.
awk -F, '{print $2,$3}' Input_file | sed 's/\([^ ]*\)\([^-]*\)-\([^-]*\)-\([^-]*\)/\1 \2 \3 \4/'
Output will be as follows.
example-string super example string
Without using sed or awk, only cut, how do I get the last field when the number of fields are unknown or change with every line?
You could try something like this:
echo 'maps.google.com' | rev | cut -d'.' -f 1 | rev
Explanation
rev reverses "maps.google.com" to be moc.elgoog.spam
cut uses dot (ie '.') as the delimiter, and chooses the first field, which is moc
lastly, we reverse it again to get com
Use a parameter expansion. This is much more efficient than any kind of external command, cut (or grep) included.
data=foo,bar,baz,qux
last=${data##*,}
See BashFAQ #100 for an introduction to native string manipulation in bash.
It is not possible using just cut. Here is a way using grep:
grep -o '[^,]*$'
Replace the comma for other delimiters.
Explanation:
-o (--only-matching) only outputs the part of the input that matches the pattern (the default is to print the entire line if it contains a match).
[^,] is a character class that matches any character other than a comma.
* matches the preceding pattern zero or more time, so [^,]* matches zero or more non‑comma characters.
$ matches the end of the string.
Putting this together, the pattern matches zero or more non-comma characters at the end of the string.
When there are multiple possible matches, grep prefers the one that starts earliest. So the entire last field will be matched.
Full example:
If we have a file called data.csv containing
one,two,three
foo,bar
then grep -o '[^,]*$' < data.csv will output
three
bar
Without awk ?...
But it's so simple with awk:
echo 'maps.google.com' | awk -F. '{print $NF}'
AWK is a way more powerful tool to have in your pocket.
-F if for field separator
NF is the number of fields (also stands for the index of the last)
There are multiple ways. You may use this too.
echo "Your string here"| tr ' ' '\n' | tail -n1
> here
Obviously, the blank space input for tr command should be replaced with the delimiter you need.
This is the only solution possible for using nothing but cut:
echo "s.t.r.i.n.g." | cut -d'.' -f2-
[repeat_following_part_forever_or_until_out_of_memory:] | cut -d'.' -f2-
Using this solution, the number of fields can indeed be unknown and vary from time to time. However as line length must not exceed LINE_MAX characters or fields, including the new-line character, then an arbitrary number of fields can never be part as a real condition of this solution.
Yes, a very silly solution but the only one that meets the criterias I think.
If your input string doesn't contain forward slashes then you can use basename and a subshell:
$ basename "$(echo 'maps.google.com' | tr '.' '/')"
This doesn't use sed or awk but it also doesn't use cut either, so I'm not quite sure if it qualifies as an answer to the question as its worded.
This doesn't work well if processing input strings that can contain forward slashes. A workaround for that situation would be to replace forward slash with some other character that you know isn't part of a valid input string. For example, the pipe (|) character is also not allowed in filenames, so this would work:
$ basename "$(echo 'maps.google.com/some/url/things' | tr '/' '|' | tr '.' '/')" | tr '|' '/'
the following implements A friend's suggestion
#!/bin/bash
rcut(){
nu="$( echo $1 | cut -d"$DELIM" -f 2- )"
if [ "$nu" != "$1" ]
then
rcut "$nu"
else
echo "$nu"
fi
}
$ export DELIM=.
$ rcut a.b.c.d
d
An alternative using perl would be:
perl -pe 's/(.*) (.*)$/$2/' file
where you may change \t for whichever the delimiter of file is
It is better to use awk while working with tabular data. You don't have to master on command. If it can be achieved by awk, why not use that? I suggest you do not waste your precious time, and use a handful of commands to get the job done.
Example:
# $NF refers to the last column in awk
ll | awk '{print $NF}'
If you have a file named filelist.txt that is a list paths such as the following:
c:/dir1/dir2/file1.h
c:/dir1/dir2/dir3/file2.h
then you can do this:
rev filelist.txt | cut -d"/" -f1 | rev
Adding an approach to this old question just for the fun of it:
$ cat input.file # file containing input that needs to be processed
a;b;c;d;e
1;2;3;4;5
no delimiter here
124;adsf;15454
foo;bar;is;null;info
$ cat tmp.sh # showing off the script to do the job
#!/bin/bash
delim=';'
while read -r line; do
while [[ "$line" =~ "$delim" ]]; do
line=$(cut -d"$delim" -f 2- <<<"$line")
done
echo "$line"
done < input.file
$ ./tmp.sh # output of above script/processed input file
e
5
no delimiter here
15454
info
Besides bash, only cut is used.
Well, and echo, I guess.
choose -1
choose supports negative indexing (the syntax is similar to Python's slices).
I realized if we just ensure a trailing delimiter exists, it works. So in my case I have comma and whitespace delimiters. I add a space at the end;
$ ans="a, b"
$ ans+=" "; echo ${ans} | tr ',' ' ' | tr -s ' ' | cut -d' ' -f2
b
I have a file with the following layout:
123,01-08-2006
124,01-09-2007
125,01-10-2009
126,01-12-2010
How can I convert it into the following by using AWK?
123,2006-08-01
124,2007-09-01
125,2009-10-01
126,2009-12-01
Didn't read the question properly the first time. You need a field separator that can be either a dash or a comma. Once you have that you can use the dash as an output field separator (as it's the most common) and fake the comma using concatenation:
awk -F',|-' 'OFS="-" {print $1 "," $4,$3,$2}' file
Pure awk
awk -F"," '{ n=split($2,b,"-");$2=b[3]"-"b[2]"-"b[1];$i=$1","$2 } 1' file
sed
sed -r 's/(^.[^,]*,)([0-9]{2})-([0-9]{2})-([0-9]{4})/\1\4-\3-\2/' file
sed 's/\(^.[^,]*,\)\([0-9][0-9]\)-\([0-9][0-9]\)-\([0-9]\+\)/\1\4-\3-\2/' file
Bash
#!/bin/bash
while IFS="," read -r a b
do
IFS="-"
set -- $b
echo "$a,$3-$2-$1"
done <"file"
Unfortunately, I think standard awk only allows one field separator character so you'll have to pre-process the data. You can do this with tr but if you really want an awk-only solution, use:
pax> echo '123,01-08-2006
124,01-09-2007
125,01-10-2009
126,01-12-2010' | awk -F, '{print $1"-"$2}' | awk -F- '{print $1","$4"-"$3"-"$2}'
This outputs:
123,2006-08-01
124,2007-09-01
125,2009-10-01
126,2010-12-01
as desired.
The first awk changes the , characters to - so that you have four fields separated with the same character (this is the bit I'd usually use tr ',' '-' for).
The second awk prints them out in the order you specified, correcting the field separators at the same time.
If you're using an awk implementation that allows multiple FS characters, you can use something like:
gawk -F ',|-' '{print $1","$4"-"$3"-"$2}'
If it doesn't need to be awk, you could use Perl too:
$ perl -nle 'print "$1,$4-$3-$2" while (/(\d{3}),(\d{2})-(\d{2})-(\d{4})\s*/g)' < file.txt