AtBS 7 Regex

Question 1

Steps into creating regex matching?

Answer 1

1. import re module

2. Create regex module with compile function
ie the d\d\d\-d\d\d\d

3. Pass the string you want into the regex search method
4. Call the match object group to return a string

Question 2

Example of phone number regex matching?

Answer 2

import re

phoneNumRegex=re.compile(r’\d\d\d-\d\d\d-\d\d\d\d’)

mo=phoneNumRegex.search(‘My number is 615-555-3244’)

print(‘Phone number found:’+mo.group())

Question 3

What is a pipe and what does it do for regex?

Answer 3

It is the | symbol

It is the or statement for regex.

Question 4

What does ? do in regex?

Answer 4

It flags the group that comes before it as an optional part to match.

Question 5

What does * do in regex?

Answer 5

It is the match for zero or more character.

Can find haha or hahaha

Question 6

What does + do in regex?

Answer 6

It is the match for one or more characters

Question 7

What do curly brackets {} do in regex?

Answer 7

they match a specific number of instances.

ex (Ha){3} matches with HaHaHa but not HaHa

Question 8

What is greedy versus nongreedy matching and how is it set?

Answer 8

greedy matching is the default state for the curly brackets with a range.

Example {3,5} will pick 5 repetitions unless you put question mark behind it.

Question 9

\d is what in regex?

Answer 9

Any numeric digit from 0 to 9

Question 10

\D is what in regex?

Answer 10

Any character that is not a numeric digit 0 to 9

Question 11

\w is what in regex?

Answer 11

Any letter, numeric digit, or the underscore character

Question 12

\W is what in regex?

Answer 12

Any character that is not a letter, numeric digit or the underscore character

Question 13

\s is what in regex?

Answer 13

Any space, tab or newline character.

Question 14

\S is what in regex?

Answer 14

Any character that is not a space, tab or a newline character.

Question 15

Example of make your own regex to find vowels only?

Answer 15

vowelRegex=re.compile(r’[aeiouAEIOU]’)

square brackets are the key

Question 16

What does caret symbol ^ do for regex?

Example

Answer 16

It finds based on what is not in a list

’[^aeiouAEIOU] would find consonants

Question 17

What can the caret and dollar sign do in regex?

Answer 17

Can make it so you need to find the search term at the beginning with the ^

or at the end of the string with a dollar sign

Question 18

What is the dot symbol . used for in regex?

Example

Answer 18

It is used to match all characters

atRegex=re.compile(r’.at’)

would match cat, bat, hat

Question 19

What does .* match?

Example

Answer 19

It matches everything

nameRegex = re.compile(r ‘ FirstName: (.*)’)

will pull all the first names