I have some code that can use regex to filter and find a list of files.
I want to filter these files by their name, and select the final set of numbers in the filename.
for example, say I have this sequence of file names:
render1frame0001.png ... render1frame0200.png
Finding the last 4 digits isnt that hard. The issue is when the file name itself has numbers in it.
Some platforms have different margins for frame counts, so I need it to be able to match more or less than 4 characters, while also ignoring any numbers in the file name.
so in the example above, it would match 0001 through 0200, ignoring the 1 inside the filename.
I dont have much experience with regex and this particular problem seems a little niche, so I dont exactly know what to do here.
also, the files can possibly have other extensions, such as jpeg, so I guess it should also be able to work around different extensions.
Essentially I want to match the first occurrence of a group of numbers... but from the end of the string backwards. That behavior could possibly get around the extension and any extra numbers in the file name.
Is this possible?
Used "Lookahead and Lookbehind" to get numeric value properly.
regex = /(?<=\w+)\d+(?=\.[a-z]+)/gi (Best) or /\d+(?=\.[a-z]+)/gi or /\d+(?=\.[a-z]+$)/gi (if you pass single file name at a time).
Your Input is: "render1frame0001.png ... render1frame0200.png".
You have to match numbers before file format ('.png').
For more details about regular expression follow this: Puzzling with Regular Expression
Since each string is a filename that include the file extension, you should be able to use the below regular expression, regardless of the file type:
(\d+)\.[a-z]+$
Regular Expression Tests
Note: since the regular expression contains the $ character, each filename should be parsed individually.
Related
I'm having some trouble putting together a regex for trimming a file name after a certain length. This is being used to rename a large number of files simultaneously, far too many to reasonably rename by hand. Unfortunately, some of our employees like to leave notes on the end of the file name, which is what we're looking to remove.
Example file names, all of these are present and are making matching problematic.
ABC - A11B11 - Note.txt
ABC - A22B22 (Note).txt
ABC - A33B33 | Note.txt
All files will be identical in length, 16 characters specifically. The 1st section will be purely letters, specifically client account names. The 2nd section is a combination of numbers and letters, case ID numbers. The makeup of the 2nd sequence varies with each file name, but are always 6 digits long, and are always a mixture of 2 letters and 4 numbers.
I've tried using regex to pinpoint the number/letter pattern in the 2nd sequence and delete everything afterwards. I've also tried leveraging the 16 character length to delete all characters beyond 16. Unfortunately, I'm not particularly good with regex and I'm not making much headway. Most of my attempts are recognized as a valid regex search, but give incorrect match results.
Any assistance I can get on this would be greatly appreciated.
The cleanest regex replacement I can conjure up would be:
Find: ^([A-Z0-9]+ - [A-Z0-9]+).*(\.\w+)$
Replace: $1$2
Demo
This approach is to match and capture the first two portions of the file name which you want to retain. It also captures the file extension. Then, in the replacement, we form the new file name, effectively removing any notes which might have followed the second section of the name.
I think I just found a working search. It's not as hands free as I was originally hoping for and will require adjusting the query for match text for different account names and do them in batches, but it works.
Find: (^ABC - A11\d{2}).*
Replace: $1
It's probably better this way anyway, making automated changes to such a wide range of business documentation makes me a little nervous. This way we can roll out changes slowly to ensure accuracy and avoid data loss or mislabeling.
Thank you for everyone that pitched in ideas.
I am using a file transferring tool that allows the use of Regular Expression to rename files as they are copied into a new folder (so I am working with Regular Expression only and not inside a code base) I have a large set of files with a specific naming convention with a version number at the end of the file name. My goal is to remove this file version number along with the underscore.
Here are some examples of the file names:
the_file_name_DS_017_EN_35.pdf
the_file_name_DS_037_SP_35.pdf
different_filename_DS_EN_5.pdf
I am looking to change them to:
the_file_name_DS_017_EN.pdf
the_file_name_DS_037_SP.pdf
different_filename_DS_EN.pdf
I am trying to remove the version number so that the file naming convention on my new server will always be the same. I am not good with regex and this is what I tried so far but to no avail:
Using _[^_]+$ it selects last underscore along with the .pdf extension.
Using \_(.*?)\. it selects the first underscore until the period.
How do I select the last underscore until the period removing that text but keeping the period? Maybe there is a better method? Thanks in advance!
If you regex motor works with positive lookaheads, you might work it like this and replace it by nothing
(_\d+)(?=\.pdf$)
Demo
Explanation :
(_\d+) will follow an underscore following by one or more digits
(?=\.pdf$) will match as a positive lookahead the .pdf extension at the end of the file name
TRY to use the regular expression here:
_[0-9]*\.
and replace it by
.
I am trying to match a series of suffixes, but, our file names often contain multiple periods for example "Document A V0.1.1.docx"
I have tried a number of solutions, but none seem to work for me and I'm not a great regex user... this is where I got to, but it fails to ignore multiple periods in the filename.
The regex will be used in the DocFetcher program to exclude large numbers of file from indexing where the suffixed filenames contents is of no use to the person using DocFetcher.
Suggestions?
(?i).*\.(jar|doc|docx|etc...)
my input strings look like this:
1 warning: rg: W, MULT: file 'filename_a.h' was listed twice.
2 warning: rg: W, SCOP: scope redefined in '/proj/test/site_a/filename_b.c'.
3 warning: rg: W, ATTC: file /proj/test/site_b/filename_c.v is not resolved.
4 warning: rg: W, MULTH: property file filename_d.vu was listed outside.
They come in four different flavors as listed above. I read these from a log file line by line.
For the one with path specified (line 2,3) I can extract filename using $file=~s#.*/##; and seems to work fine. Is there a way not to use conditional statements for different type and extract the filename? I want to use just one clean regex and extract the filename. Perl's File::basename will not work also in this case.
I am using Perl.
You could do it in two steps:
extract path from each line
get basename from the path
Example
#!/usr/bin/perl -n
use feature 'say';
use File::Basename;
#NOTE: assume that unquoted path has no spaces in it
say basename($1.$2) if /(?:file|redefined in)\s+(?:'([^']+)'|(\S+))/;
Output
filename_a.h
filename_b.c
filename_c.v
filename_d.vu
Your problem needs more constraints. For example, what's a good way to characterize a string as a "path" (or "filename") or not? You might say, "Hey, when I see a single dot immediately followed by letters and numbers (but not symbols), and there are a bunch of characters before that dot too, then it might be a path or filename!"
\s+([^\s]+\.\w+)
But this doesn't catch all paths, nor files without an extension. So we might latch on an alternation to say, "Either the above, or, a string with at least one slash in it."
\s+([^\s]+\.\w+|[^\s]*\/[^\s]*)
(Note that you may not need to escape the slash in the above example, since you seem to be using # as your delimiter.)
What I'm getting at, in any case, is that you need to specify your problem more rigorously, and this will automatically bring you to a satisfying solution. Of course, there is no truly "correct" solution using regexes alone: you'd need to do file tests to do that.
To go further with this example, perhaps you want to define a list of extensions:
\s+([^\s]+\.(?:c|h|cc|cpp)|[^\s]*\/[^\s]*)
Or, perhaps you want to be more generic, but allow only extensions up to 4 characters long:
\s+([^\s]+\.\w{1,4}|[^\s]*\/[^\s]*)
Perhaps you only consider something a path if it begins with a slash, but you still want at least one another slash somewhere in it:
\s+([^\s]+\.\w{1,4}|/[^\s]*\/[^\s]*)
Good luck.
/\w*.\w*/
This will match the file name expressed in the four different warning logs. \w will match any word character (letters, digits, and underscores), so this regex looks for any number of word characters, followed by a dot followed by more word characters.
This works because the only other dot in your logs is at the end of the log.
How can I use regex to find all text before the text "All text before this line will be included"?
I have includes some sample text below for example
This can include deleting, updating, or adding records to your database, which would then be reflex.
All text before this line will be included
You can make this a bit more sophisticated by encrypting the random number and then verifying that it is still a number when it is decrypted. Alternatively, you can pass a value and a key instead.
Starting with an explanation... skip to end for quick answers
To match upto a specific piece of text, and confirm it's there but not include it with the match, you can use a positive lookahead, using notation (?=regex)
This confirms that 'regex' exists at that position, but matches the start position only, not the contents of it.
So, this gives us the expression:
.*?(?=All text before this line will be included)
Where . is any character, and *? is a lazy match (consumes least amount possible, compared to regular * which consumes most amount possible).
However, in almost all regex flavours . will exclude newline, so we need to explicitly use a flag to include newlines.
The flag to use is s, (which stands for "Single-line mode", although it is also referred to as "DOTALL" mode in some flavours).
And this can be implemented in various ways, including...
Globally, for /-based regexes:
/regex/s
Inline, global for the regex:
(?s)regex
Inline, applies only to bracketed part:
(?s:reg)ex
And as a function argument (depends on which language you're doing the regex with).
So, probably the regex you want is this:
(?s).*?(?=All text before this line will be included)
However, there are some caveats:
Firstly, not all regex flavours support lazy quantifiers - you might have to use just .*, (or potentially use more complex logic depending on precise requirements if "All text before..." can appear multiple times).
Secondly, not all regex flavours support lookaheads, so you will instead need to use captured groups to get the text you want to match.
Finally, you can't always specify flags, such as the s above, so may need to either match "anything or newline" (.|\n) or maybe [\s\S] (whitespace and not whitespace) to get the equivalent matching.
If you're limited by all of these (I think the XML implementation is), then you'll have to do:
([\s\S]*)All text before this line will be included
And then extract the first sub-group from the match result.
(.*?)All text before this line will be included
Depending on what particular regular expression framework you're using, you may need to include a flag to indicate that . can match newline characters as well.
The first (and only) subgroup will include the matched text. How you extract that will again depend on what language and regular expression framework you're using.
If you want to include the "All text before this line..." text, then the entire match is what you want.
This should do it:
<?php
$str = "This can include deleting, updating, or adding records to your database, which would then be reflex.
All text before this line will be included
You can make this a bit more sophisticated by encrypting the random number and then verifying that it is still a number when it is decrypted. Alternatively, you can pass a value and a key instead.";
echo preg_filter("/(.*?)All text before this line will be included.*/s","\\1",$str);
?>
Returns:
This can include deleting, updating, or adding records to your database, which would then be reflex.