I have a string, let's say, jkdfkskjak some random string containing a desired word
I want to check if the given string has a word from a set of words, say {word1, word2, word3} in latex.
I can easily do it in Java, but I want to achieve it using regex. I am very new to regular expressions.
if you want only to recognise the words as part of a word, then use:
(word1|word2|...|wordn)
(see first demo)
if you want them to appear as isolated words, then
\b(word1|word2|...|wordn)\b
should be the answer (see second demo)
I am not able to understand the complete context like what kind of text you have or what kind of words will this be but I can offer you a easy solution the literal way programmatically you can generate this regex (dormammu|bargain) and then search this in text like this "dormammu I come to bargain". I have no clue about latex but I think that is not your question.
For more information you can tinker with it at [regex101][1].
If you are having trouble understanding it [regexone][2] this is the place to go. For beginners its a good start.
[1]: http://regex101.com [2]: https://regexone.com/
I want to find and replace text between to hash comments. e.g I want to find if there is a text something like below within #string_start and #string_end
#string_start
this could be any text here
and here
#string_end
I tried this code but it didn't work and I know I am not using the corrent syntax due to my lack of regex knowledge.
\#string_start(.*?)\#string_end
#string_start\n([\s\S]*?)#string_end
Try this.Grab the capture.See demo.
https://regex101.com/r/vD5iH9/61
I am trying to make an if-then-else statement using RegEx. I want to match the text if it contains Monty and also contains Python. Also the text should get matched if Monty is not present in the text.
RegEx
(?(?=Monty)(?(?=Python).*|)|^.*).*$
Kindly help!
How about this:
(^(?!.*Monty(?!.*Python.*).*).*$|^.*Python.*Monty.*$)
This passes my tests, but let me know if it works for you.
I am not versed in lookahead regex but just tried to build the regex from what I understood from above description. Check the link to see if this is what you are trying to do.
try this instead
((?=Monty)((?=Python).*|)|^.*).*$
Let presume we have something like this:
<div1>
<h1>text1</h1>
<h1>text2</h1>
</div1>
<div2>
<h1>text3</h1>
</div2>
Using RegExp we need to get text1 and text2 but not text3.
How to do this?
Thanks in advance.
EDIT:
This is just an example.
The text I'm parsing could be just plain text.
The main thing I want to accomplish is list all strings from a specific section of a document.
I gave this HTML code for example as it perfectly resembles the thing I need to get.
(?siU)<h1>(.*)</h1> would parse all three strings, but how to get only first two?
EDIT2:
Here is another rather dumb example. :)
Section1
This is a "very" nice sentence.
It has "just" a few words.
Section2
This is "only" an example.
The End
I need quoted words from first but not from second section.
Yet again, (?siU)"(.*)" returns quoted words from whole text,
and I need only those between words Section1 and Section2.
This is for the "Rainmeter" application, which apparently uses Perl regex syntax.
I'm sorry, but I can't explain it better. :)
For the general case of the two examples provided -- for use in Rainmeter regex -- you can use:
(?siU)<h1>(.*)</h1>(?=.+<div2>) for the first sample and
(?siU)"(.*)"(?=.+Section2) for the second.
Note that Rainmeter seems to escape things for you, but you might need to change " to \", above.
These both use Positive Lookahead but beware: both solutions will fail in the case of nested tags/structures or if there are mutiple Section1's and Section2's. Regex is not the best tool for this kind of parsing.
But maybe this is good enough for your current needs?
Use a DOM library and getElementsByTagName('div') and you'll get a nodeList back. You can reference the first item with ->item(0) and then getElementsByTagName('h1') using the div as a context node, grab the text with ->nodeValue property.
I want to get just the filename using regex, so I've been trying simple things like
([^\.]*)
which of course work only if the filename has one extension. But if it is adfadsfads.blah.txt I just want adfadsfads.blah. How can I do this with regex?
In regards to David's question, 'why would you use regex' for this, the answer is, 'for fun.' In fact, the code I'm using is simple
length_of_ext = File.extname(filename).length
filename = filename[0,(filename.length-length_of_ext)]
but I like to learn regex whenever possible because it always comes up at Geek cocktail parties.
Try this:
(.+?)(\.[^.]*$|$)
This will:
Capture filenames that start with a dot (e.g. .logs is a file named .logs, not a file extension), which is common in Unix.
Gets everything but the last dot: foo.bar.jpeg gets you foo.bar.
Handles files with no dot: secret-letter gets you secret-letter.
Note: as commenter j_random_hacker suggested, this performs as advertised, but you might want to precede things with an anchor for readability purposes.
Everything followed by a dot followed by one or more characters that's not a dot, followed by the end-of-string:
(.+?)\.[^\.]+$
The everything-before-the-last-dot is grouped for easy retrieval.
If you aren't 100% sure every file will have an extension, try:
(.+?)(\.[^\.]+$|$)
how about 2 captures one for the end and one for the filename.
eg.
(.+?)(?:\.[^\.]*$|$)
^(.*)\\(.*)(\..*)$
Gets the Path without the last \
The file without extension
The the extension with a .
Examples:
c:\1\2\3\Books.accdb
(c:\1\2\3)(Books)(.accdb)
Does not support multiple . in file name
Does support . in file path
I realize this question is a bit outdated, however, I had some trouble finding a good source and wound up making the regex myself. To save whoever may find this time,
If you're looking for a ~standalone~ regex
This will match the extension without the dot
\w+(?![\.\w])
This will always match the file name if it has an extention
[\w\. ]+(?=[\.])
Ok, I am not sure why I would use regular expression for this. If I know for example that the string is a full filepath, then I would use another API to get the file name. Regular expressions are very powerfull but at the same time quite complex (you have just proved that by asking how to create such a simple regex). Somebody said: you had a problem that you decided to solve it using regular expressions. Now you have two problems.
Think again. If you are on .NET platform for example, then take a look at System.IO.Path class.
I used this pattern for simple search:
^\s*[^\.\W]+$
for this text:
file.ext
fileext
file.ext.ext
file.ext
fileext
It finds fileext in the second and last lines.
I applied it in a text tree view of a folder (with spaces as indents).
Just the name of the file, without path and suffix.
^.*[\\|\/](.+?)\.[^\.]+$
Try
(?<=[\\\w\d-:]*\\)([\w\d-:]*)(?=\.[\.\w\d-:]*)
Captures just the filename of any kind within an entire filepath. Purposefully excludes the file path and the file extension
Etc:
C:\Log\test\bin\fee105d1-5008-410c-be39-883e5e40a33d.pdf
Doesn't capture (C:\Log\test\bin)
Captures (fee105d1-5008-410c-be39-883e5e40a33d)
Doesn't capture (.pdf)
This RegExp works for me:
(.+(?=\..+$))|(.+[^\.])
Results (bold means match):
test.txt
test 234!.something123
.test
.test.txt
test.test2.txt
.