class MathLibError(Exception):
    """Base class for all mathlib exceptions."""
    pass

class DomainError(MathLibError):
    """Raised when arguments are outside allowed mathematical domain."""
    pass


class ZeroDivisionMathError(MathLibError):
    """Raised when division by zero is attempted."""
    pass


class ConvergenceError(MathLibError):
    """Raised when an iterative algorithm fails to converge."""
    pass