String in Python Note

1. String value

String is a collection of alphabets, words or other characters. String represent in double quote " " or single quote ' '

Example:

• firstName = "Rady"
• lastName = "Y"
• schoolName = 'PNC'
• studentName = 'Bopha'
• text = "Hello world in 1995"

String conversion

Convert integer, float and boolean to string

• floatNumber = 10.5 ➡️ string = str(floatNumber) // "10.5"
• number = 10 ➡️ string = str(number) // "10"
• isBoolean = True ➡️ string = string(isBoolean) // "True"
• isBoolean = False ➡️ string = string(isBoolean) // "False"

2. Input in Python

• string = input()
• string = str(input())
• number = int(input())
• number = float(input())

3. Output in Python

• print("Hello world")
• print(100)
• print(10.5)
• print(True)
• number = 10 ➡️ print(number)
• string = 'rady' ➡️ print(string)
• number = 10.5 ➡️ print(number)
• hasNumber = False ➡️ print(hasNumber)

4. String accessability in Python

To access a string we use [] sign and index of each character starting from 0

• text = "ABC" ➡️ text[0] // A
• text = "ABC" ➡️ text[1] // B
• text = "ABC" ➡️ text[2] // C
• text = "ABC" ➡️ text[3] // IndexError: string index out of range

5. String function in Python

• string = "abc" ➡️ len(string) // 3
• string = "abc" ➡️ string.upper() // ABC
• string = "aBc" ➡️ string.lower() // abc
• string = "abc" ➡️ string.isupper() // False
• string = "abc" ➡️ string.isLower() // True
• string = "abc" ➡️ string.isnumeric() // False
• string = "12" ➡️ string.isnumeric() // True
• number = 12 ➡️ str(number) // "12"

6. String concatination

• string = "A" + "B" // AB
• string = "5" + "6" // 56
• string = 10 + "7" // TypeError: unsupported operand type(s) for +: 'int' and 'str'
• string = 5.6 + "A" // TypeError: unsupported operand type(s) for +: 'float' and 'str'
• string = str(100) + "8" // 1008

7. String looping

For loop iteration by default incrementing from 0 it th same index of string

# Python
text = "abc"
for i in range(len(text)):
    print(text[i])

# Output of code above:
a
b
c

Other ways to loop

# Python
text = "abc"
i = 0
while i < len(text):
    print(text[i])
    i = i + 1

# Output of code above:
a
b
c