Lesson 4.1 Strings

Strings in Python:

Printing

• you can print the string directly or use variables to store it

#printing directly, use single or double qutoes:
print("panda")


#variable = "string"
animal = "rabbit"
#keep variable descriptive of what value it holds to make code easier to read
#single or double quotes both work

#variables with multiple words, use underscore not space
favorite_animal = "otter"

#don't use quotes when using variables
print(animal)
print(favorite_animal)

panda
rabbit
otter

Quotes:

• if using single quotes and string has a single quote, python will read it as the end of a string
• to combat this, use a backslash or double quotes
• vice versa for double quotes

# example:  mood1 = 'I'm feeling tired'
#apostrophe in "I'm" interrupts string and will cause error

#use backslash in front or double quotes
mood2 = 'I\'m feeling happy'
mood3 = "I'm feeling sad"

print(mood2)
print(mood3)

I'm feeling happy
I'm feeling sad

Strings with multiple lines

• instead of printing 3 separate strings, use 3 quotes
  • both single and double work

riddle = """my favorite animal
hiberates during the winter
in a cave"""

print(riddle)

my favorite animal
hiberates during the winter
in a cave

len function

• stands for length
• returns length of a string

print(len ("hummingbird"))

11

Printing specific parts of a string

• for a specific character: use []
• for a range: use [ : ]
  • starts counting at 0
  • first value is inclusive, second is not
• slicing:
  • leaving first value empty: will start at 0
  • leaving second value empty: will end with last character

tiger_fact = "the stripes on a tiger are unique, similar to human fingerprints"

#specific character: 
print(tiger_fact[5])

#range:
print(tiger_fact[4:11])

#slicing:
print(tiger_fact[:23])
print(tiger_fact[35:])

t
stripes
the stripes on a tiger 
similar to human fingerprints

Palindromes

A palindrome is a string that reads the same from right to left as left to right.

Ex: 2112, mom, taco cat

def palindrome(input_str):
    # Remove spaces and convert the string to lowercase
    clean_str = input_str.replace(" ", "").lower()
    # Check if the cleaned string is equal to its reverse
    return clean_str == clean_str[::-1]


print(palindrome("go hang a salami im a lasagna hog")) # True
print(palindrome("hi")) # False

True
False