TheAlgorithms/Python · error · ValueError

Wrong space!

Error message

Wrong space!

What it means

Error "Wrong space!" thrown in TheAlgorithms/Python.

Source

Thrown at maths/numerical_analysis/bisection_2.py:40

    9.99
    """
    return 10 - x * x


def bisection(a: float, b: float) -> float:
    """
    >>> bisection(-2, 5)
    3.1611328125
    >>> bisection(0, 6)
    3.158203125
    >>> bisection(2, 3)
    Traceback (most recent call last):
        ...
    ValueError: Wrong space!
    """
    # Bolzano theory in order to find if there is a root between a and b
    if equation(a) * equation(b) >= 0:
        raise ValueError("Wrong space!")

    c = a
    while (b - a) >= 0.01:
        # Find middle point
        c = (a + b) / 2
        # Check if middle point is root
        if equation(c) == 0.0:
            break
        # Decide the side to repeat the steps
        if equation(c) * equation(a) < 0:
            b = c
        else:
            a = c
    return c


if __name__ == "__main__":
    import doctest

View on GitHub (pinned to f5988cc097)

Solutions

1. Pass an interval where the function changes sign (f(a)*f(b) < 0).
2. Verify the interval bounds are ordered and bracket a root.

When it happens

Trigger: Thrown at maths/numerical_analysis/bisection_2.py:40 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of TheAlgorithms/Python@f5988cc097 (2026-08-14). Data as JSON: /api/errors/28953f1097f76a6c. Report an issue: GitHub.