TheAlgorithms/Python · error · TypeError

Input values must either be float or int: {list(locals().val

Error message

Input values must either be float or int: {list(locals().values())}

What it means

Raised by convert_to_2d (graphics/vector3_for_2d_rendering.py:32) when any of its five arguments (x, y, z, distance, scale) is not a float or int. The function performs 3D-to-2D perspective projection arithmetic, so all five values must be numeric before the projection formulas run.

Source

Thrown at graphics/vector3_for_2d_rendering.py:32

    x: float, y: float, z: float, scale: float, distance: float
) -> tuple[float, float]:
    """
    Converts 3d point to a 2d drawable point

    >>> convert_to_2d(1.0, 2.0, 3.0, 10.0, 10.0)
    (7.6923076923076925, 15.384615384615385)

    >>> convert_to_2d(1, 2, 3, 10, 10)
    (7.6923076923076925, 15.384615384615385)

    >>> convert_to_2d("1", 2, 3, 10, 10)  # '1' is str
    Traceback (most recent call last):
        ...
    TypeError: Input values must either be float or int: ['1', 2, 3, 10, 10]
    """
    if not all(isinstance(val, (float, int)) for val in locals().values()):
        msg = f"Input values must either be float or int: {list(locals().values())}"
        raise TypeError(msg)
    projected_x = ((x * distance) / (z + distance)) * scale
    projected_y = ((y * distance) / (z + distance)) * scale
    return projected_x, projected_y


def rotate(
    x: float, y: float, z: float, axis: str, angle: float
) -> tuple[float, float, float]:
    """
    rotate a point around a certain axis with a certain angle
    angle can be any integer between 1, 360 and axis can be any one of
    'x', 'y', 'z'

    >>> rotate(1.0, 2.0, 3.0, 'y', 90.0)
    (3.130524675073759, 2.0, 0.4470070007889556)

    >>> rotate(1, 2, 3, "z", 180)
    (0.999736015495891, -2.0001319704760485, 3)

View on GitHub (pinned to f5988cc097)

Solutions

1. Convert each argument at the call site: convert_to_2d(float(x), float(y), float(z), float(distance), float(scale))
2. Sanitize incoming data once at the boundary (parser/config loader), not at every call
3. If using Decimal/Fraction, convert to float first — the function only accepts the built-in numeric types

Example fix

# before
point_2d = convert_to_2d(row["x"], row["y"], row["z"], distance, scale)  # row values are str

# after
point_2d = convert_to_2d(
    float(row["x"]), float(row["y"]), float(row["z"]),
    float(distance), float(scale),
)

x, y, z, distance, scale = (float(v) for v in (x, y, z, distance, scale))
projected = convert_to_2d(x, y, z, distance, scale)

def all_numeric(*vals: object) -> bool:
    return all(isinstance(v, (int, float)) and not isinstance(v, bool) for v in vals)

try:
    p = convert_to_2d(x, y, z, d, s)
except TypeError as exc:
    raise ValueError(f"bad 3D point data: {exc}") from exc

When it happens

Trigger: convert_to_2d("1", 2, 3, 10, 10) — one string poisons all inputs; also None, lists, or bools (bool passes the check since bool subclasses int, which can silently produce 1/0 coordinates).

Common situations: Reading coordinates from JSON/CSV where numbers arrive as strings; passing values straight from a GUI form or argparse without float(); passing Decimal or Fraction objects that are numeric but not int/float instances.

Related errors

• Axis must be a str
• Input values except axis must either be float or int: {list(
• Input value must be a positive integer
• Input value must be a 'int' type
• Input value must be a 'int' type

AI-assisted analysis of TheAlgorithms/Python@f5988cc097 (2026-08-14). Data as JSON: /api/errors/d488d2899b1a2077. Report an issue: GitHub.