TheAlgorithms/Python · error · TypeError

'str' object cannot be interpreted as an integer

Error message

'str' object cannot be interpreted as an integer

What it means

decimal_to_any raises TypeError('str' object cannot be interpreted as an integer') when the base argument is a str. The message matches CPython's int(x, '16') error on purpose. The base feeds divmod(num, base), which cannot work with strings; note this check runs after the num sign check, so a negative num with a str base raises the num error first.

Source

Thrown at conversions/decimal_to_any.py:65

        ...
    TypeError: 'str' object cannot be interpreted as an integer
    >>> # a base less than 2 will error
    >>> decimal_to_any(7, 0) # doctest: +ELLIPSIS
    Traceback (most recent call last):
        ...
    ValueError: base must be >= 2
    >>> # a base greater than 36 will error
    >>> decimal_to_any(34, 37) # doctest: +ELLIPSIS
    Traceback (most recent call last):
        ...
    ValueError: base must be <= 36
    """
    if isinstance(num, float):
        raise TypeError("int() can't convert non-string with explicit base")
    if num < 0:
        raise ValueError("parameter must be positive int")
    if isinstance(base, str):
        raise TypeError("'str' object cannot be interpreted as an integer")
    if isinstance(base, float):
        raise TypeError("'float' object cannot be interpreted as an integer")
    if base in (0, 1):
        raise ValueError("base must be >= 2")
    if base > 36:
        raise ValueError("base must be <= 36")
    new_value = ""
    mod = 0
    div = 0
    while div != 1:
        div, mod = divmod(num, base)
        if base >= 11 and 9 < mod < 36:
            actual_value = ALPHABET_VALUES[str(mod)]
        else:
            actual_value = str(mod)
        new_value += actual_value
        div = num // base
        num = div

View on GitHub (pinned to f5988cc097)

Solutions

1. Cast the base: decimal_to_any(34, int(base_str))
2. Configure CLI parsing with type=int: argparse.add_argument('-b', type=int)
3. Validate 2 <= int(base) <= 36 after casting (the function also checks range)

Example fix

# before
decimal_to_any(34, '16')
# TypeError: 'str' object cannot be interpreted as an integer

# after
decimal_to_any(34, int('16'))  # '22'

base = int(base)  # raises early if not numeric
decimal_to_any(num, base)

def is_valid_base(b) -> bool:
    return isinstance(b, int) and not isinstance(b, bool) and 2 <= b <= 36

try:
    decimal_to_any(num, base)
except TypeError as e:
    if 'cannot be interpreted as an integer' in str(e):
        return decimal_to_any(num, int(base))
    raise

When it happens

Trigger: decimal_to_any(34, '16') — very common when CLI args or json values are not cast; decimal_to_any(34, '0x10'); passing a base typed by a user as text.

Common situations: argparse without type=int; JSON config where base was quoted; interactive input() left as a string; wrapping the function with **kwargs passed through from text sources.

Related errors

• int() can't convert non-string with explicit base
• parameter must be positive int
• operation can not be conducted on an object of type {type(nu
• Input value must be an 'int' type
• plaintext must be a string

AI-assisted analysis of TheAlgorithms/Python@f5988cc097 (2026-08-14). Data as JSON: /api/errors/4a5420dca60d8450. Report an issue: GitHub.