11.3. Regexp Search

11.3.1. About

• re.search()

• Searches if pattern contains a string

11.3.2. Examples

Listing 11.3. Usage of re.search()

import re


def contains(pattern, text)
    if re.search(pattern, text):
        return True
    else:
        return False


COMMIT_MESSAGE = 'MYPROJ-1337, MYPROJ-997 removed obsolete comments'
JIRA_ISSUEKEY = r'[A-Z]{2,10}-[0-9]{1,6}'
REDMINE_NUMBER = r'#[0-9]+'

contains(JIRA_ISSUEKEY, COMMIT_MESSAGE)      # True
contains(REDMINE_NUMBER, COMMIT_MESSAGE)     # False

11.3.3. Assignments

11.3.3.1. Regexp Search

• Complexity level: easy

• Lines of code to write: 6 lines

• Estimated time of completion: 5 min

• Solution: solution/search_astronauts.py

• References: First paragraph from Apollo 11 Wikipedia entry [re-2]

English

1. Download data/apollo11-header.txt and save as search_astronauts.txt

2. Use re.search() to check if Astronaut first and last names are in the text

3. Astronauts to find:

   • Neil Armstrong

   • Buzz Aldrin

   • Michael Collins

   • Jan Twardowski

   • Mark Watney

Polish

1. Pobierz data/apollo11-header.txt i zapisz jako search_astronauts.txt

2. Użyj re.search() do sprawdzenia czy imiona i nazwiska Astronautów występują w tekście

3. Astronauts do znalezienia:

   • Neil Armstrong

   • Buzz Aldrin

   • Michael Collins

   • Jan Twardowski

   • Mark Watney

11.3.3.2. Moon Speech (search)

• Complexity level: easy

• Lines of code to write: 5 lines

• Estimated time of completion: 10 min

• Solution: solution/search_moon_speech.py

• References: "Moon Speech" by John F. Kennedy at Rice Stadium, Houston, TX on 1962-09-12 [re-1]

English

1. Download "Moon Speech" text data/moon_speech.html

2. Save as moon_speech.html

3. Using re.search() split text by paragraphs

4. Print paragraph starting with "We choose to go to the moon"

Polish

1. Pobierz tekst przemówienia "Moon Speech" data/moon_speech.html

2. Zapisz jako moon_speech.html

3. Za pomocą re.search() podziel tekst na paragrafy

4. Wyświetl paragraf zaczynający się od słów "We choose to go to the moon"

11.3.3.3. Search for Any Time

• Complexity level: medium

• Lines of code to write: 4 lines

• Estimated time of completion: 5 min

• Solution: solution/search_time_any.py

• References: First paragraph from Apollo 11 Wikipedia entry [re-2]

English

1. Download data/apollo11-header.txt and save as search_astronauts.txt

2. Use regular expressions to check text contains time in UTC (format: %H:%M UTC)

3. Use simplified checking: ##:## UTC, where # is a digit

4. Print found time

Polish

1. Pobierz data/apollo11-header.txt i zapisz jako search_astronauts.txt

2. Użyj wyrażeń regularnych do sprawdzenia czy tekst zawiera godzinę w UTC (format: %H:%M UTC)

3. Użyj uproszczonego sprawdzania: ##:## UTC, gdzie # to dowolna cyfra

4. Print found time

11.3.3.4. Search for Valid Time

• Complexity level: hard

• Lines of code to write: 4 lines

• Estimated time of completion: 15 min

• Solution: solution/search_time_valid.py

• References: (modified) First paragraph from Apollo 11 Wikipedia entry [re-2]

English

1. Use data from "Input" section (see below)

2. Use regular expressions to check text contains time in UTC (format: %H:%M UTC)

3. Note, that this is slightly modified text than previously

4. Check if text contains time in UTC (format: %H:%M UTC)

5. Found match must be a valid time

6. Print found time

Polish

1. Użyj danych z sekcji "Input" (patrz poniżej)

2. Użyj wyrażeń regularnych do sprawdzenia czy tekst zawiera godzinę w UTC (format: %H:%M UTC)

3. Zwróć uwagę, że to lekko zmodyfikowany tekst niż poprzednio

4. Sprawdź czy tekst zawiera godzinę w UTC (format: %H:%M UTC)

5. Znalezisko musi być poprawnym czasem

6. Wyświetl znaleziony czas

Input

Listing 11.4. (modified) First paragraph from Apollo 11 Wikipedia entry [re-2]

Apollo 11 was the spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin formed the American crew that landed the Apollo Lunar Module Eagle on July 20, 1969, at 20:67 UTC. Armstrong became the first person to step onto the lunar surface six hours and 39 minutes later on July 21 at 02:56 UTC; Aldrin joined him 19 minutes later. They spent about two and a quarter hours together outside the spacecraft, and they collected 47.5 pounds (21.5 kg) of lunar material to bring back to Earth. Command module pilot Michael Collins flew the command module Columbia alone in lunar orbit while they were on the Moon's surface. Armstrong and Aldrin spent 21 hours, 36 minutes on the lunar surface at a site they named Tranquility Base before lifting off to rejoin Columbia in lunar orbit.