Splitting string containing letters and numbers not separated by any particular delimiter in PHP
algorithm, nlp, php, regex, string
Solution
You can use preg_split
$string = "Hi, my name is Bob. I m 19yo and 170cm tall";
$parts = preg_split("/(,?\s+)|((?<=[a-z])(?=\d))|((?<=\d)(?=[a-z]))/i", $string);
var_dump ($parts);
When matching against the digit-letter boundary, the regular expression match must be zero-width. The characters themselves must not be included in the match. For this the zero-width lookarounds are useful.
http://codepad.org/i4Y6r6VS
Problem
Currently I am developing a web application to fetch Twitter stream and trying to create a natural language processing by my own. Since my data is from Twitter (limited by 140 characters) there are many words shortened, or on this case, omitted space. For example: ``` "Hi, my name is Bob. I m 19yo and 170cm tall" ``` Should be tokenized to: ``` - hi - my - name - bob - i - 19 - yo - 170 - cm - tall ``` Notice that `19` and `yo` in `19yo` have no space between them. I use it mostly for extracting numbers with their units. Simply, what I need is a way to 'explode' each tokens that has number in it by chunk of numbers or letters without delimiter. `'123abc'` will be `['123', 'abc']` `'abc123'` will be `['abc', '123']` `'abc123xyz'` will be `['abc', '123', 'xyz']` and so on. What is the best way to achieve it in PHP? I found something close to it, but it's C# and spesifically for day/month splitting. How do I split a string in C# based on letters and numbers