Regular Expression or Regex-NLP

Regular Expression or Regex is basically a tool which we use to find pattern or find word, character or sentence in sequence of character. Here is the analogy:

You have been an overflowing inbox of emails and you want specific email to show up your criteria for it is:

• Find all emails with meeting.
• Find all emails with dollar amount.
• Spot all the emails which contains word like URGENT and IMPORTANT.

Now you can't open email one by one because it will take forever. So you decided setup a Smart Filter using rules like:

• If emails contains '$' sign then it must be finance show me.
• If emails have date or word like meeting show me.
• If subject contains ‘URGENT’ followed by ! marks, show me.

This exactly Regex do for NLP:

It acts like a smart filter for text — scanning through messy, unstructured language and pulling out what you’re interested in, based on patterns.

In coming lecture I will be explaining about regex.