Ciao guys,
I'm creating a corpus composed with tweets that contain the keyword "catastrophic" in XML format. Each tweet are embedded like this:
<tweet>"Catastrophic loss" at Tennessee's Zoo Knoxville as 33 reptiles are found dead </tweet>
<tweet>Overcoming Catastrophic Forgetting by Incremental Moment Matching, Lee et al.</tweet
After trimming tons of unnecessary data, there are still like 200+ tweets that don't contain the keyword at all. I'd like to delete them, so I tried regex like this, but it just didn't work:
<tweet>^.*(?!catastrophic).*$</tweet>
Does anybody has any idea?
Not sure what programming language or other toolset you are using.
But a quite simple approach might be to re-write the file (or whatever kind of input it is) using a filter that only writes the entries that do contain catastrophic:
Assuming that it is a file with one line per tweet (just to illustrate the idea):
egrep '<tweet>.*catastrophic.*</tweet>' originalFile > newFile
Related
I have a string variable containing school names and I need to find all the possible combination of each word in this string variable in stata:
For example variation of a word "Academy" would be:
Academy,
Academy,
acdamey,
aacdemy,
dmcaamy,
aacedmy,
and so on.
I need this to standardize the raw data of school names, which has many typos of each word due to data entry issues, like the ones given above for "academy".
Depending whether your data is already in the Excel sheets or a file, you can either use regex trying to match all possible combinations (and probably fix them when found) or parse the strings first before bringing them into Excel. In either case you could make a file (or Excel list/table/area/etc.) that includes all the common typos and pick each typo as regex match to use when comparing to your actual input.
Making regexp that would actually find all possible cases is next to impossible, especially if there are cases where very similar (but correct) names for schools exist. In any case direct regexps would be very messy and complex, so I would advice you to parse the data by finding first the correct form, excluding it and then using (greedy) search/regex to find the typoed versions. You can then save the typos to use them as a filter/match/pattern.
To get some sort of starting ideas, check this links:
Regex: Search for verb roots
Read text file and extract string into Excel sheet using regex
P.s You should keep the count of all strings/school names and finally get a list of all names that did not match correct form or any of your regexp filters, so you can manually insert/correct them.
As I stated on the title.
I'm try to find regex result on a specific word(like apple) having random newline(\r\n) special character.
Illustrate more detail...
Let's find a word 'apple' on the text file. but We don't know where is exact position of newline(\r\n) on the file like below...
ap
ple
or
appl
e
I also googled many pages but I couldn't find the answer.
Should I have to write beginner regex like below?
(a\r\npple|ap\r\nple|app\r\nle|appl\r\ne|apple\r\n|)
I need to find more smarter regex to find exact word.
updated.
the word can be vary like "ripe apple", "rotten apple" and "brightapple".
In the case of third item, white space removed by writer.
updated
i have many txt files. i have to find the string within those.
So remove /r/n is not useful and cannot handle(too much menory and time required).
You have to take the naive approach ("beginner regex") if you want to use regular expressions, since they belong to the type 3 grammars and cannot express the state needed (see also The difference between Chomsky type 3 and Chomsky type 2 grammar)
I have one .ics file from which I would like to create individual new .ics files depending on the event categories (I can't get egroupware to export only events of one category, I want to create new calendars depending on category). My intended approach is to repeatedly eliminate all events but those of one category and then save the file using EditPad Lite 7 (Windows).
I am struggling to get the regular expression right. .+? is still too greedy and negating the string (e.g. to eliminate all but events from one category) doesn't work either.
Sample
BEGIN:VEVENT
DESCRIPTION:Event 2
END:VEVENT
BEGIN:VEVENT
DESCRIPTION:Event 3
CATEGORIES:Sports
END:VEVENT
BEGIN:VEVENT
DESCRIPTION:Event 4
END:VEVENT
The regex BEGIN:VEVENT.+?CATEGORIES:Sports.+?END:VEVENT should only match sports events but it catches everything from the first BEGINto the first ENDfollowing the category.
Edit: negating doesn't work either: BEGIN:VEVENT.+?((?!CATEGORIES:Sports).).+?END:VEVENT.
What am I missing? Any pointers are highly appreciated.
I guess newlines are removed or ignored, because your regex does not care about them.
I only have a correction to the match after CATEGORIES
BEGIN:VEVENT.+?CATEGORIES:Sports.*?END:VEVENT
^
Zero or more
The first part of your regex looks good, maybe the regex engine in EditPad is not so good.
Try it with a different editor or scripting language (like Eclipse or perl or Notepad+ or Notepad2)
You could split the input and then grep the matching Sports events
#sportevents = grep /Sports/, split /END:VEVENT/, $input
map $_.="END:VEVENT", #sportevents
This was perl, maybe you can launch a script from EditPad to do it.
The second line just restores the END:VEVENT that was stripped during split.
OK. Solved it. I found something here which can be used to split ics files. I tweaked it to use the category rather than the summary in the file name and then merged the individually generated files according to category. I added the usual ics header and footer to all files and, voilà, I had individual calendar files.
I have a txt file that I’m trying to import as flat file into SQL2008 that looks like this:
“123456”,”some text”
“543210”,”some more text”
“111223”,”other text”
etc…
The file has more than 300.000 rows and the text is large (usually 200-500 chars), so scanning the file by hand is very time consuming and prone to error. Other similar (and even more complex files) were successfully imported.
The problem with this one, is that “some lines” contain quotes in the text… (this came from an export from an old SuperBase DB that didn’t let you specify a text quantifier, there’s nothing I can do with the file other than clear it and try to import it).
So the “offending” lines look like this:
“123456”,”this text “contains” a quote”
“543210”,”And the “above” text is bad”
etc…
You can see the problem here.
Now, 300.000 is not too much if I could perform a search using a text editor that can use regex, I’d manually remove the quotes from each line. The problem is not the number of offending lines, but the impossibility to find them with a simple search. I’m sure there are less than 500, but spread those in a 300.000 lines txt file and you know what I mean.
Based upon that, what would be the best regex I could use to identify these lines?
My first thought is: Tell me which lines contain more than 4 quotes (“).
But I couldn’t come up with anything (I’m not good at Regex beyond the basics).
this pattern ^("[^"]+){4,} will match "lines containing more than 4 quotes"
you can experiment with replacing 4 with 5 or more, depending on your data.
I think that you can be more direct with a Regex than you're planning to be. Depending on your dialect of Regex, something like this should do it:
^"\d+",".*".*"
You could also use a regex to remove the outside quotes and use a better delimeter instead. For example, search for ^"([0-9]+)","(.*)"$ and replace it with \1+++++DELIM+++++\2.
Of course, this doesn't directly answer your question, but it might solve the problem.
I recently discussed editors with a co-worker. He uses one of the less popular editors and I use another (I won't say which ones since it's not relevant and I want to avoid an editor flame war). I was saying that I didn't like his editor as much because it doesn't let you do find/replace with regular expressions.
He said he's never wanted to do that, which was surprising since it's something I find myself doing all the time. However, off the top of my head I wasn't able to come up with more than one or two examples. Can anyone here offer some examples of times when they've found regex find/replace useful in their editor? Here's what I've been able to come up with since then as examples of things that I've actually had to do:
Strip the beginning of a line off of every line in a file that looks like:
Line 25634 :
Line 632157 :
Taking a few dozen files with a standard header which is slightly different for each file and stripping the first 19 lines from all of them all at once.
Piping the result of a MySQL select statement into a text file, then removing all of the formatting junk and reformatting it as a Python dictionary for use in a simple script.
In a CSV file with no escaped commas, replace the first character of the 8th column of each row with a capital A.
Given a bunch of GDB stack traces with lines like
#3 0x080a6d61 in _mvl_set_req_done (req=0x82624a4, result=27158) at ../../mvl/src/mvl_serv.c:850
strip out everything from each line except the function names.
Does anyone else have any real-life examples? The next time this comes up, I'd like to be more prepared to list good examples of why this feature is useful.
Just last week, I used regex find/replace to convert a CSV file to an XML file.
Simple enough to do really, just chop up each field (luckily it didn't have any escaped commas) and push it back out with the appropriate tags in place of the commas.
Regex make it easy to replace whole words using word boundaries.
(\b\w+\b)
So you can replace unwanted words in your file without disturbing words like Scunthorpe
Yesterday I took a create table statement I made for an Oracle table and converted the fields to setString() method calls using JDBC and PreparedStatements. The table's field names were mapped to my class properties, so regex search and replace was the perfect fit.
Create Table text:
...
field_1 VARCHAR2(100) NULL,
field_2 VARCHAR2(10) NULL,
field_3 NUMBER(8) NULL,
field_4 VARCHAR2(100) NULL,
....
My Regex Search:
/([a-z_])+ .*?,?/
My Replacement:
pstmt.setString(1, \1);
The result:
...
pstmt.setString(1, field_1);
pstmt.setString(1, field_2);
pstmt.setString(1, field_3);
pstmt.setString(1, field_4);
....
I then went through and manually set the position int for each call and changed the method to setInt() (and others) where necessary, but that worked handy for me. I actually used it three or four times for similar field to method call conversions.
I like to use regexps to reformat lists of items like this:
int item1
double item2
to
public void item1(int item1){
}
public void item2(double item2){
}
This can be a big time saver.
I use it all the time when someone sends me a list of patient visit numbers in a column (say 100-200) and I need them in a '0000000444','000000004445' format. works wonders for me!
I also use it to pull out email addresses in an email. I send out group emails often and all the bounced returns come back in one email. So, I regex to pull them all out and then drop them into a string var to remove from the database.
I even wrote a little dialog prog to apply regex to my clipboard. It grabs the contents applies the regex and then loads it back into the clipboard.
One thing I use it for in web development all the time is stripping some text of its HTML tags. This might need to be done to sanitize user input for security, or for displaying a preview of a news article. For example, if you have an article with lots of HTML tags for formatting, you can't just do LEFT(article_text,100) + '...' (plus a "read more" link) and render that on a page at the risk of breaking the page by splitting apart an HTML tag.
Also, I've had to strip img tags in database records that link to images that no longer exist. And let's not forget web form validation. If you want to make a user has entered a correct email address (syntactically speaking) into a web form this is about the only way of checking it thoroughly.
I've just pasted a long character sequence into a string literal, and now I want to break it up into a concatenation of shorter string literals so it doesn't wrap. I also want it to be readable, so I want to break only after spaces. I select the whole string (minus the quotation marks) and do an in-selection-only replace-all with this regex:
/.{20,60} /
...and this replacement:
/$0"¶ + "/
...where the pilcrow is an actual newline, and the number of spaces varies from one incident to the next. Result:
String s = "I recently discussed editors with a co-worker. He uses one "
+ "of the less popular editors and I use another (I won't say "
+ "which ones since it's not relevant and I want to avoid an "
+ "editor flame war). I was saying that I didn't like his "
+ "editor as much because it doesn't let you do find/replace "
+ "with regular expressions.";
The first thing I do with any editor is try to figure out it's Regex oddities. I use it all the time. Nothing really crazy, but it's handy when you've got to copy/paste stuff between different types of text - SQL <-> PHP is the one I do most often - and you don't want to fart around making the same change 500 times.
Regex is very handy any time I am trying to replace a value that spans multiple lines. Or when I want to replace a value with something that contains a line break.
I also like that you can match things in a regular expression and not replace the full match using the $# syntax to output the portion of the match you want to maintain.
I agree with you on points 3, 4, and 5 but not necessarily points 1 and 2.
In some cases 1 and 2 are easier to achieve using a anonymous keyboard macro.
By this I mean doing the following:
Position the cursor on the first line
Start a keyboard macro recording
Modify the first line
Position the cursor on the next line
Stop record.
Now all that is needed to modify the next line is to repeat the macro.
I could live with out support for regex but could not live without anonymous keyboard macros.