How to convert numeric characters in ASCII

ASCII values of numeric characters 0-9 and conversion methods:

ASCII Values of Numeric Characters:

• '0': 48
• '1': 49
• '2': 50
• '3': 51
• '4': 52
• '5': 53
• '6': 54
• '7': 55
• '8': 56
• '9': 57

Conversion Methods:

1. Numeric Character to Integer:

python
char = '5'
num = ord(char) - ord('0')  # 5
# or
num = ord(char) - 48  # 5

2. Integer to Numeric Character:

python
num = 5
char = chr(num + ord('0'))  # '5'
# or
char = chr(num + 48)  # '5'

3. Check if Character is a Digit:

python
char = '5'
is_digit = '0' <= char <= '9'  # True
# or
is_digit = 48 <= ord(char) <= 57  # True

4. Batch Conversion Examples:

python
# String to Integer
num_str = "123"
num = 0
for c in num_str:
    num = num * 10 + (ord(c) - ord('0'))
# num = 123

# Integer to String
num = 123
if num == 0:
    num_str = "0"
else:
    num_str = ""
    while num > 0:
        num_str = chr(num % 10 + ord('0')) + num_str
        num //= 10
# num_str = "123"

Important Notes:

• ASCII values of numeric characters are consecutive
• Verify character validity before conversion
• Additional logic needed for handling negative numbers