Lesson 7: Working with Text (Strings)

Text in Python is called a string. A string behaves like a list of characters, so you can pick letters by position, starting at 0.

word = "Himalaya"
print(word[0])
print(word[-1])
print(len(word))

Output:

H
a
8

Slicing

text[start:stop] takes the part from start up to (not including) stop.

word = "Himalaya"
print(word[0:4])
print(word[4:])
print(word[::-1])

Output:

Hima
laya
ayalamiH

Useful methods

sentence = "  Learn Python every day  "
clean = sentence.strip()
print(clean.upper())
print(clean.replace("Python", "coding"))
print(clean.split())

Output:

LEARN PYTHON EVERY DAY
Learn coding every day
['Learn', 'Python', 'every', 'day']

Searching

text = "Mount Everest is in Nepal"
print("Everest" in text)
print(text.find("Nepal"))
print(text.count("e"))

Output:

True
20
3

Strings cannot be changed in place. Methods like upper() give you a new string, so store the result in a variable if you want to keep it.

A small example: is it a palindrome?

word = "madam"
if word == word[::-1]:
    print(word, "is a palindrome")
else:
    print(word, "is not a palindrome")

Output:

madam is a palindrome

Try it yourself

1. Count how many vowels are in your name.
2. Turn "ram shrestha" into "Ram Shrestha" (look up title()).
3. Check whether an email address contains an @ sign.

Next lesson: grouping code into reusable functions.