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In this source code example, we will write a code to convert a binary value to its decimal equivalent in Python.

Python - Convert Binary to Decimal Example

def bin_to_decimal(bin_string: str) -> int:
    bin_string = str(bin_string).strip()
    if not bin_string:
        raise ValueError("Empty string was passed to the function")
    is_negative = bin_string[0] == "-"
    if is_negative:
        bin_string = bin_string[1:]
    if not all(char in "01" for char in bin_string):
        raise ValueError("Non-binary value was passed to the function")
    decimal_number = 0
    for char in bin_string:
        decimal_number = 2 * decimal_number + int(char)
    return -decimal_number if is_negative else decimal_number

if __name__ == "__main__":
    # Convert a binary value to its decimal equivalent
    print(bin_to_decimal("101"))
    print(bin_to_decimal(" 1010   "))
    print(bin_to_decimal("-11101"))

Output: