Remove one-character words that don't contain "a, i, and o" - bash

I'm creating a shell script that will convert stdin and output to stdout. Currently I have it converting everything to lowercase. I need to also remove single character words that are not "a", "i", or "o".
Here's what I've tried:
grep -o '[a-z]\{2,\}' | while read WORD
This successfully removes all single letter words.
Here's the desire,
./file.sh < myText.txt
Given that myText.txt has something like,
"Sample text t I o im"
Output:
sample text i o im
If awk, sed or other bash built-ins work better, I'd love to hear it.
Any help is appreciated, just trying to learn.

Here is one solution if one word per line is ok (like your going-in example did):
echo "Sample text t I o im" | \
tr '[:upper:]' '[:lower:]' | \
grep -o '\([a-z]\{2,\}\|i\|o\|a\)'

If perl is your option, how about:
perl -lane 'print join(" ", grep {tr /A-Z/a-z/; !/^[^aio]$/} #F)' myText.txt
Output:
sample text i o im

Using only GNU sed, if that's allowed,
sed -E '
s/.*/\L&/
s/(^|\s)[bcdefghjklmnpqrstuvwxyz]($|\s)/ /g
' <<< 'Sample text t I o im'
prints
sample text i o im

Related

convert a file content using shell script

Hello everyone I'm a beginner in shell coding. In daily basis I need to convert a file's data to another format, I usually do it manually with Text Editor. But I often do mistakes. So I decided to code an easy script who can do the work for me.
The file's content like this
/release201209
a1,a2,"a3",a4,a5
b1,b2,"b3",b4,b5
c1,c2,"c3",c4,c5
to this:
a2>a3
b2>b3
c2>c3
The script should ignore the first line and print the second and third values separated by '>'
I'm half way there, and here is my code
#!/bin/bash
#while Loops
i=1
while IFS=\" read t1 t2 t3
do
test $i -eq 1 && ((i=i+1)) && continue
echo $t1|cut -d\, -f2 | { tr -d '\n'; echo \>$t2; }
done < $1
The problem in my code is that the last line isnt printed unless the file finishes with an empty line \n
And I want the echo to be printed inside a new CSV file(I tried to set the standard output to my new file but only the last echo is printed there).
Can someone please help me out? Thanks in advance.
Rather than treating the double quotes as a field separator, it seems cleaner to just delete them (assuming that is valid). Eg:
$ < input tr -d '"' | awk 'NR>1{print $2,$3}' FS=, OFS=\>
a2>a3
b2>b3
c2>c3
If you cannot just strip the quotes as in your sample input but those quotes are escaping commas, you could hack together a solution but you would be better off using a proper CSV parsing tool. (eg perl's Text::CSV)
Here's a simple pipeline that will do the trick:
sed '1d' data.txt | cut -d, -f2-3 | tr -d '"' | tr ',' '>'
Here, we're just removing the first line (as desired), selecting fields 2 & 3 (based on a comma field separator), removing the double quotes and mapping the remaining , to >.
Use this Perl one-liner:
perl -F',' -lane 'next if $. == 1; print join ">", map { tr/"//d; $_ } #F[1,2]' 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.
-n : Loop over the input one line at a time, assigning it to $_ by default.
-l : Strip the input line separator ("\n" on *NIX by default) before executing the code in-line, and append it when printing.
-a : Split $_ into array #F on whitespace or on the regex specified in -F option.
-F',' : Split into #F on comma, rather than on whitespace.
SEE ALSO:
perldoc perlrun: how to execute the Perl interpreter: command line switches

Convert first character to capital along with special character separator

I would like to convert first character to capital and character coming after dash(-) needs to be converted to capital using bash.
I can split individual elements using - ,
echo "string" | tr [:lower:] [:upper:]
and join all but that doesn't seem effect. Is there any easy way to take care of this using single line?
Input string:
JASON-CONRAD-983636
Expected string:
Jason-Conrad-983636
I recommend using Python for this:
python3 -c 'import sys; print("-".join(s.capitalize() for s in sys.stdin.read().split("-")))'
Usage:
capitalize() {
python3 -c 'import sys; print("-".join(s.capitalize() for s in sys.stdin.read().split("-")))'
}
echo JASON-CONRAD-983636 | capitalize
Output:
Jason-Conrad-983636
In pure bash (v4+) without any third party utils
str=JASON-CONRAD-983636
IFS=- read -ra raw <<<"$str"
final=()
for str in "${raw[#]}"; do
first=${str:0:1}
rest=${str:1}
final+=( "${first^^}${rest,,}" )
done
and print the result
( IFS=- ; printf '%s\n' "${final[*]}" ; )
This might work for you (GNU sed):
sed 's/.*/\L&/;s/\b./\u&/g' file
Lowercase everything. Uppercase first characters of words.
Alternative:
sed -E 's/\b(.)((\B.)*)/\u\1\L\2/g' file
Could you please try following(in case you are ok with awk).
var="JASON-CONRAD-983636"
echo "$var" | awk -F'-' '{for(i=1;i<=NF;i++){$i=substr($i,1,1) tolower(substr($i,2))}} 1' OFS="-"
Although the party is mostly over, please let me join with a perl solution:
perl -pe 's/(^|-)([^-]+)/$1 . ucfirst lc $2/ge' <<<"JASON-CONRAD-983636"
It may be cunning to use the ucfirst function :)

How to use sed to extract a string [duplicate]

This question already has answers here:
BASH extract value after string in variable Not file [duplicate]
(2 answers)
Closed last year.
I need to extract a number from the output of a command: cmd. The output is type: 1000
So my question is how to execute the command, store its output in a variable and extract 1000 in a shell script. Also how do you store the extracted string in a variable?
This question has been answered in pieces here before, it would be something like this:
line=$(sed -n '2p' myfile)
echo "$line"
if [ `echo $line || grep 'type: 1000' ` ] then;
echo "It's there!";
fi;
Store output of sed into a variable
String contains in Bash
EDIT: sed is very limited, you would need to use bash, perl or awk for what you need.
This is a typical use case for grep:
output=$(cmd | grep -o '[0-9]\+')
You can write the output of a command or even a pipeline of commands into a shell variable using so called command substitution:
variable=$(cmd);
In comments it appeared that the output of cmd contains more lines than the type : 1000. In this case I would suggest sed:
output=$(cmd | sed -n 's/type : \([0-9]\+\)/\1/p;q')
You tagged your question as sed but your question description does not restrict other tools, so here's a solution using awk.
output = `cmd | awk -F':' '/type: [0-9]+/{print $2}'`
Alternatively, you can use the newer $( ) syntax. Some find the newer syntax preferable and it can be conveniently nested, without the need for escaping backtics.
output = $(cmd | awk -F':' '/type: [0-9]+/{print $2}')
If the output is rigidly restricted to "type: " followed by a number, you can just use cut.
var=$(echo 'type: 1000' | cut -f 2 -d ' ')
Obviously you'll have to pipe the output of your command to cut, I'm using echo as a demo.
In addition, I'd use grep and then cut if the string you are searching is more complex. If we assume there can be all kind of numbers in the text, but only one occurrence of "type: " followed by a number, you can use the command:
>> var=$(echo "hello 12 type: 1000 foo 1001" | grep -oE "type: [0-9]+" | cut -f 2 -d ' ')
>> echo $var
1000
You can use the | operator to send the output of one command to another, like so:
echo " 1\n 2\n 3\n" | grep "2"
This sends the string " 1\n 2\n 3\n" to the grep command, which will search for the line containing 2. It sound like you might want to do something like:
cmd | grep "type"
Here is a plain sed solution that uses a regualar expression to find the number in your string:
cmd | sed 's/^.*type: \([0-9]\+\)/\1/g'
^ means from the start
.* can be any character (also none)
\([0-9]\+\) are numbers (minimum one character)
\1 means it takes the first pattern it finds (and only in this case) and uses it as replacement for the whole string

Bash command to extract characters in a string

I want to write a small script to generate the location of a file in an NGINX cache directory.
The format of the path is:
/path/to/nginx/cache/d8/40/32/13febd65d65112badd0aa90a15d84032
Note the last 6 characters: d8 40 32, are represented in the path.
As an input I give the md5 hash (13febd65d65112badd0aa90a15d84032) and I want to generate the output: d8/40/32/13febd65d65112badd0aa90a15d84032
I'm sure sed or awk will be handy, but I don't know yet how...
This awk can make it:
awk 'BEGIN{FS=""; OFS="/"}{print $(NF-5)$(NF-4), $(NF-3)$(NF-2), $(NF-1)$NF, $0}'
Explanation
BEGIN{FS=""; OFS="/"}. FS="" sets the input field separator to be "", so that every char will be a different field. OFS="/" sets the output field separator as /, for print matters.
print ... $(NF-1)$NF, $0 prints the penultimate field and the last one all together; then, the whole string. The comma is "filled" with the OFS, which is /.
Test
$ awk 'BEGIN{FS=""; OFS="/"}{print $(NF-5)$(NF-4), $(NF-3)$(NF-2), $(NF-1)$NF, $0}' <<< "13febd65d65112badd0aa90a15d84032"
d8/40/32/13febd65d65112badd0aa90a15d84032
Or with a file:
$ cat a
13febd65d65112badd0aa90a15d84032
13febd65d65112badd0aa90a15f1f2f3
$ awk 'BEGIN{FS=""; OFS="/"}{print $(NF-5)$(NF-4), $(NF-3)$(NF-2), $(NF-1)$NF, $0}' a
d8/40/32/13febd65d65112badd0aa90a15d84032
f1/f2/f3/13febd65d65112badd0aa90a15f1f2f3
With sed:
echo '13febd65d65112badd0aa90a15d84032' | \
sed -n 's/\(.*\([0-9a-f]\{2\}\)\([0-9a-f]\{2\}\)\([0-9a-f]\{2\}\)\)$/\2\/\3\/\4\/\1/p;'
Having GNU sed you can even simplify the pattern using the -r option. Now you won't need to escape {} and () any more. Using ~ as the regex delimiter allows to use the path separator / without need to escape it:
sed -nr 's~(.*([0-9a-f]{2})([0-9a-f]{2})([0-9a-f]{2}))$~\2/\3/\4/\1~p;'
Output:
d8/40/32/13febd65d65112badd0aa90a15d84032
Explained simple the pattern does the following: It matches:
(all (n-5 - n-4) (n-3 - n-2) (n-1 - n-0))
and replaces it by
/$1/$2/$3/$0
You can use a regular expression to separate each of the last 3 bytes from the rest of the hash.
hash=13febd65d65112badd0aa90a15d84032
[[ $hash =~ (..)(..)(..)$ ]]
new_path="/path/to/nginx/cache/${BASH_REMATCH[1]}/${BASH_REMATCH[2]}/${BASH_REMATCH[3]}/$hash"
Base="/path/to/nginx/cache/"
echo '13febd65d65112badd0aa90a15d84032' | \
sed "s|\(.*\(..\)\(..\)\(..\)\)|${Base}\2/\3/\4/\1|"
# or
# sed sed 's|.*\(..\)\(..\)\(..\)$|${Base}\1/\2/\3/&|'
Assuming info is a correct MD5 (and only) string
First of all - thanks to all of the responders - this was extremely quick!
I also did my own scripting meantime, and came up with this solution:
Run this script with a parameter of the URL you're looking for (www.example.com/article/76232?q=hello for example)
#!/bin/bash
path=$1
md5=$(echo -n "$path" | md5sum | cut -f1 -d' ')
p3=$(echo "${md5:0-2:2}")
p2=$(echo "${md5:0-4:2}")
p1=$(echo "${md5:0-6:2}")
echo "/path/to/nginx/cache/$p1/$p2/$p3/$md5"
This assumes the NGINX cache has a key structure of 2:2:2.

Get string between strings in bash

I want to get the string between <sometag param=' and '>
I tried to use the method from Get any string between 2 string and assign a variable in bash to get the "x":
echo "<sometag param='x'><irrelevant stuff='nonsense'>" | tr "'" _ | sed -n 's/.*<sometag param=_\(.*\)_>.*/\1/p'
The problem (apart from low efficiency because I just cannot manage to escape the apostrophe correctly for sed) is that sed matches the maximum, i.e. the output is:
x_><irrelevant stuff=_nonsense
but the correct output would be the minimum-match, in this example just "x"
Thanks for your help
You are probably looking for something like this:
sed -n "s/.*<sometag param='\([^']*\)'>.*/\1/p"
Test:
echo "<sometag param='x'><irrelevant stuff='nonsense'>" | sed -n "s/.*<sometag param='\([^']*\)'>.*/\1/p"
Results:
x
Explanation:
Instead of a greedy capture, use a non-greedy capture like: [^']* which means match anything except ' any number of times. To make the pattern stick, this is followed by: '>.
You can also use double quotes so that you don't need to escape the single quotes. If you wanted to escape the single quotes, you'd do this:
-
... | sed -n 's/.*<sometag param='\''\([^'\'']*\)'\''>.*/\1/p'
Notice how that the single quotes aren't really escaped. The sed expression is stopped, an escaped single quote is inserted and the sed expression is re-opened. Think of it like a four character escape sequence.
Personally, I'd use GNU grep. It would make for a slightly shorter solution. Run like:
... | grep -oP "(?<=<sometag param=').*?(?='>)"
Test:
echo "<sometag param='x'><irrelevant stuff='nonsense'>" | grep -oP "(?<=<sometag param=').*?(?='>)"
Results:
x
You don't have to assemble regexes in those cases, you can just use ' as the field separator
in="<sometag param='x'><irrelevant stuff='nonsense'>"
IFS="'" read x whatiwant y <<< "$in" # bash
echo "$whatiwant"
awk -F\' '{print $2}' <<< "$in" # awk

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