I want to replace value 2000 with 5000 for the fruit grapes. How to use sed to start searching from 'grapes' position and replace the first occurance
<fruits>
<fruit>
<name>apple</name>
<value>2000</value>
</fruit>
<fruit>
<name>grapes</name>
<value>2000</value>
</fruit>
<fruit>
<name>banana</name>
<value>2000</value>
</fruit>
</fruits>
I tried
sed '\,grapes, s/2000/5000/' fruits.txt
sed -i '\%<name>grapes</name>%,\%</fruit>%s%<value>2000</value>%<value>5000</value>%' fruits.xml
We use the generalized \% to avoid needing to backslash the slash in the closing tags. The s%%% doesn't need to be backslashed because sed already knows that the thing after s is the separator.
On *BSDish platforms, including MacOS, you need an explicit empty string argument to sed -i before the script itself (so sed -i '' '\%...')
This tries to be strict, but of course cannot cope with all the possible variations which are syntactically allowed in XML. If your file is always in exactly the expected format, this should work for now. One of the drawbacks is that you will get no warning when it stops working because Jenkins decides to start using whitespace inside the tags, or whatever.
Using xmlstarlet:
xmlstarlet ed -u "//fruits/fruit/name[.='grapes']/following-sibling::value" -v 5000 fruits.xml
This will update (ed -u) the xml by selecting the xpath //fruits/fruit/name where name is grapes and where the following-sibling is value, changing the content to 5000.
sed is for doing s/old/new that is all. For anything else you should be using awk:
$ awk '/grapes/{f=1} f && sub(/2000/,"5000"){f=0} 1' file
<fruits>
<fruit>
<name>apple</name>
<value>2000</value>
</fruit>
<fruit>
<name>grapes</name>
<value>5000</value>
</fruit>
<fruit>
<name>banana</name>
<value>2000</value>
</fruit>
</fruits>
Related
I'm trying to learn sed but getting stuck when trying to replace first word wih the 3rd. I was thinking about the above code, but it doesn't work.
Also, is there any way of splitting the line if the words are separated by ":" using sed?
sed "s/\(^[a-z,0-9]*\) \(.*\) \([a-z,0-9]*\)/\1 \2 \1/"
From your comment below it sounds like you actually want to replace the third word with the first one rather than the other way around. If so then:
$ echo 'first:second:third' | sed 's/\(\([^:]*\).*:\).*/\1\2/'
first:second:first
or if you have many fields to manipulate:
$ echo 'first:second:third' | sed 's/\([^:]*\):\([^:]*\):\([^:]*\)/\1:\2:\1/'
first:second:first
but you should really use awk for anything involving fields anyway:
$ echo 'first:second:third' | awk 'BEGIN{FS=OFS=":"} {$3=$1} 1'
first:second:first
I'm having issues matching strings even if they start with any number of white spaces. It's been very little time since I started using regular expressions, so I need some help
Here is an example. I have a file (file.txt) that contains two lines
#String1='Test One'
String1='Test Two'
Im trying to change the value for the second line, without affecting line 1 so I used this
sed -i "s|String1=.*$|String1='Test Three'|g"
This changes the values for both lines. How can I make sed change only the value of the second string?
Thank you
With gnu sed, you match spaces using \s, while other sed implementations usually work with the [[:space:]] character class. So, pick one of these:
sed 's/^\s*AWord/AnotherWord/'
sed 's/^[[:space:]]*AWord/AnotherWord/'
Since you're using -i, I assume GNU sed. Either way, you probably shouldn't retype your word, as that introduces the chance of a typo. I'd go with:
sed -i "s/^\(\s*String1=\).*/\1'New Value'/" file
Move the \s* outside of the parens if you don't want to preserve the leading whitespace.
There are a couple of solutions you could use to go about your problem
If you want to ignore lines that begin with a comment character such as '#' you could use something like this:
sed -i "/^\s*#/! s|String1=.*$|String1='Test Three'|g" file.txt
which will only operate on lines that do not match the regular expression /.../! that begins ^ with optional whiltespace\s* followed by an octothorp #
The other option is to include the characters before 'String' as part of the substitution. Doing it this way means you'll need to capture \(...\) the group to include it in the output with \1
sed -i "s|^\(\s*\)String1=.*$|\1String1='Test Four'|g" file.txt
With GNU sed, try:
sed -i "s|^\s*String1=.*$|String1='Test Three'|" file
or
sed -i "/^\s*String1=/s/=.*/='Test Three'/" file
Using awk you could do:
awk '/String1/ && f++ {$2="Test Three"}1' FS=\' OFS=\' file
#String1='Test One'
String1='Test Three'
It will ignore first hits of string1 since f is not true.
Below is the content of ma file (sample.txt):
CQUAD4 5600000 560005 5602371 5602367 5602374 5602372 0. -1.75
CQUAD4 5600003 560005 5600000 5602367 5602374 5602372 0. -1.75
Am using the below command:
sed -i "s#\(\s*\w*\s*\)\(5600000\)\(\s*\)\([0-9]*\)\(.*\)#\1\2\36000 \5#g" sample.txt
I want to restrict the pattern matching 5600000 to only second column and then do a replace with '6000 '.
Can somebody help me...please
Here's a possible solution with GNU sed. Anchor the search to start of line with ^.
sed -i -r "s#^(\s*\S+\s+)5600000\s+#\16000 #" sample.txt
awk might be a little more natural for this:
awk '$2=="5600000"{$2="6000";print} 1' sample.txt
That basically says "if the second field is 5600000, replace it with 6000 and print the line, otherwise just print the line".
The one downside I see is that this might, depending on your version of awk, collapse multiple spaces down to one, which may mess with the alignment of your columns. You'll have to decide if that's a problem or not...
I have a data file that needs to have several uniq identifiers stripped of hyphens.
So I have:
(Special_Section "data-values")
and I want to have it replaced with:
(Special_Section "datavalues")
I wanted to use a simple sed find/replace, but the data and values are different each time. Preferably, I'd run this in-place since the file has a lot of other information I want to keep in tact.
Does sed or awk have a way to remove the hyphen from the matched portion only?
Currently I can match with: sed -i 's/Special_Section "[a-zA-Z0-9]*-[a-zA-Z0-9]*"/&/g *myfiles*
But I would like to then run s/-// on & if it's possible.
You seems to be using GNU sed, so something like this might work:
sed -ri '
s/(Special_Section [^-]*)-([^)]*)/\1\2/g
' <your_filename_glob>
does this work?
sed -i '/(Special_Section ".*-.*")/{s/-//}' yourFile
Close - scan for the lines and then substitute on those that match:
sed -i '/Special_Section "[a-zA-Z0-9]*-[a-zA-Z0-9]*"/s/\( "[a-zA-Z0-9]*\)-\([a-zA-Z0-9]*\)"/\1\2/' *myfiles*
You can split that over several lines to avoid the scroll bar in SO:
sed -i '/Special_Section "[a-zA-Z0-9]*-[a-zA-Z0-9]*"/{
s/\( "[a-zA-Z0-9]*\)-\([a-zA-Z0-9]*\)"/\1\2/
}' *myfiles*
And on further thoughts, you can also do:
sed -i 's/\(Special_Section "[a-zA-Z0-9]*\)-\([a-zA-Z0-9]*"\)/\1\2/' *myfiles*
This is more compact. You can add the g qualifier if you need it. Both solutions use the special \(...\) notation to capture parts of the regular expression.
I have many lines of the form
ko04062 ko:CXCR3
ko04062 ko:CX3CR1
ko04062 ko:CCL3
ko04062 ko:CCL5
ko04080 ko:GZMA
and would dearly like to get rid of the ko: bit of the right-hand column. I'm trying to use sed, as follows:
echo "ko05414 ko:ITGA4" | sed 's/\(^ko\d{5}\)\tko:\(.*$\)/\1\2/'
which simply outputs the original string I echo'd. I'm very new to command line scripting, sed, pipes etc, so please don't be too angry if/when I'm doing something extremely dumb.
The main thing that is confusing me is that the same thing happens if I reverse the \1\2 bit to read \2\1 or just use one group. This, I guess, implies that I'm missing something about the mechanics of piping the output of echo into sed, or that my regexp is wrong or that I'm using sed wrong or that sed isn't printing the results of the substitution.
Any help would be greatly appreciated!
sed is outputting its input because the substitution isn't matching. Since you're probably using GNU sed, try this:
echo "ko05414 ko:ITGA4" | sed 's/\(^ko[0-9]\{5\}\)\tko:\(.*$\)/\1\2/'
\d -> [0-9] since GNU sed doesn't recognize \d
{} -> \{\} since GNU sed by default uses basic regular expressions.
This should do it. You can also skip the last group and simply use, \1 instead, but since you're learning sed and regex this is good stuff. I wanted to use a non-capturing group in the middle (:? ) but I could not get that to play with sed for whatever reason, perhaps it's not supported.
sed --posix 's/\(^ko[0-9]\{5\}\)\( ko:\)\(.*$\)/\1 \3/g' file > result
And ofcourse you can use
sed --posix 's/ko://'
You don't need sed for this
Here is how you can do it with bash:
var="ko05414 ko:ITGA4"
echo ${var//"ko:"}
${var//"ko:"} replaces all "ko:" with ""
See Manipulating Strings for more info
#OP, if you just want to get rid of "ko:", then
$ cat file
ko04062 ko:CXCR3
ko04062 ko:CX3CR1
ko04062 ko:CCL3
ko04062 ko:CCL5
some text with a legit ko: this ko: will be deleted if you use gsub.
ko04080 ko:GZMA
$ awk '{sub("ko:","",$2)}1' file
ko04062 CXCR3
ko04062 CX3CR1
ko04062 CCL3
ko04062 CCL5
some text with a legit ko: this ko: will be deleted if you use gsub.
ko04080 GZMA
Jsut a note. While you can use pure bash string substitution, its only more efficient when you are changing a single string. If you have a file, especially a big file, using bash's while read loop is still slower than using sed or awk.