Regex to extract acronyms

Question

I am using regex to extract acronyms(only specific types) from text in python.

• ABC (all caps within round brackets or square brackets or between word endings)
• A.B.C (same as above but having only one '.' in between)
• A&B&C (same as above but having only one '&' in between)

So far I am using

text = "My name is STEVE. My friend works at (I.A.). Indian Army(IA). B&W also B&&W Also I...A"
re.findall('\\b[A-Z][A-Z.&]{2,7}\\b', text)

Output is : ['STEVE', 'I.A', 'B&W', 'B&&W', 'I...A']
I want to exclude B&&W and I..A, but include (IA). 

I am aware of the below links but I am unable to use them correctly. Kindly help.

Extract acronyms patterns from string using regex

Finding Acronyms Using Regex In Python

RegEx to match acronyms

Answer 1

What you want is a capital followed by a bunch of capitals, with optional dots or ampersands in between.

re.findall('\\b[A-Z](?:[\\.&]?[A-Z]){1,7}\\b', text)

Breaking it down:

• All back slashes are doubled because they need escaping
• \b word border
• [A-Z] capital
• (?: opening a non-capturing group
• [\.&] character class containing . and &
• ? optional
• [A-Z] followed by another capital
• ) closing non-capturing group of an optional . or &, followed by a capital
• {1,7} repeating that group 1 - 7 times
• \b word border

We want a non-capturing group since re.findall returns groups (if present).

There are better ways of matching capitals that work across all of the Unicode characters.

This does match B&WW and B&W.W, since we do not enforce the use of the (same) character every time. If you want that, the expression gets a bit more complex (though not much).