Reputation: 159
I am working on twitter data normalization. Twitter users frequently uses terms like ts I looooooove it in order to emphasize the word love. I want to such repeated characters to a proper English word by replacing repeat characters till I get a proper meaningful word (I am aware that I can not differentiate between good and god by this mechanism).
My strategy would be
identify existence of such repeated strings. I would look for more than 2 same characters, as probably there is no English word with more than two repeat characters.
String[] strings = { "stoooooopppppppppppppppppp","looooooove", "good","OK", "boolean", "mee", "claaap" };
String regex = "([a-z])\\1{2,}";
Pattern pattern = Pattern.compile(regex);
for (String string : strings) {
Matcher matcher = pattern.matcher(string);
if (matcher.find()) {
System.out.println(string+" TRUE ");
}
}
Search for such words in a Lexicon like Wordnet
Due to my poor Java knowledge I am unable to manage 3 and 4. Problem is I can not replace all but two repeated consecutive characters.
Following code snippet replace all but one repeated characters System.out.println(data.replaceAll("([a-zA-Z])\\1{2,}", "$1"));
Help is required to find out A. How to replace all but 2 consecutive repeat characters B. How to remove one more consecutive character from the output of A [I think B can be managed by the following code snippet]
System.out.println(data.replaceAll("([a-zA-Z])\\1{1,}", "$1"));
Edit: Solution provided by Wiktor Stribiżew works perfectly in Java. I was wondering what changes are required to get the same result in python. Python uses re.sub.
Upvotes: 3
Views: 8184
Reputation: 627607
Your regex ([a-z])\\1{2,}
matches and captures an ASCII letter into Group 1 and then matches 2 or more occurrences of this value. So, all you need to replace with a backreference, $1
, that holds the value captured. If you use one $1
, the aaaaa
will be replaced with a single a
and if you use $1$1
, it will be replaced with aa
.
String twoConsecutivesOnly = data.replaceAll(regex, "$1$1");
String noTwoConsecutives = data.replaceAll(regex, "$1");
See the Java demo.
If you need to make your regex case insensitive, use "(?i)([a-z])\\1{2,}"
or even "(\\p{Alpha})\\1{2,}"
. If any Unicode letters must be handled, use "(\\p{L})\\1{2,}"
.
BONUS: In a general case, to replace any amount of any repeated consecutive chars use
text = text.replaceAll("(?s)(.)\\1+", "$1"); // any chars
text = text.replaceAll("(.)\\1+", "$1"); // any chars but line breaks
text = text.replaceAll("(\\p{L})\\1+", "$1"); // any letters
text = text.replaceAll("(\\w)\\1+", "$1"); // any ASCII alnum + _ chars
Upvotes: 3
Reputation: 1
/*This code checks a character in a given string repeated consecutively 3 times
if you want to check for 4 consecutive times change count==2--->count==3 OR
if you want to check for 2 consecutive times change count==2--->count==1*/
public class Test1 {
static char ch;
public static void main(String[] args) {
String str="aabbbbccc";
char[] charArray = str.toCharArray();
int count=0;
for(int i=0;i<charArray.length;i++){
if(i!=0 ){
if(charArray[i]==ch)continue;//ddddee
if(charArray[i]==charArray[i-1]) {
count++;
if(count==2){
System.out.println(charArray[i]);
count=0;
ch=charArray[i];
}
}
else{
count=0;//aabb
}
}
}
}
}
Upvotes: 0