def _init_from_bool(self, z, x):
        """Construct pauli from boolean array.

        Args:
            z (numpy.ndarray): boolean, z vector
            x (numpy.ndarray): boolean, x vector

        Returns:
            Pauli: self

        Raises:
            QiskitError: if z or x are None or the length of z and x are different.
        """
        if z is None:
            raise QiskitError("z vector must not be None.")
        if x is None:
            raise QiskitError("x vector must not be None.")
        if len(z) != len(x):
            raise QiskitError("length of z and x vectors must be "
                              "the same. (z: {} vs x: {})".format(len(z), len(x)))

        z = _make_np_bool(z)
        x = _make_np_bool(x)
        self._z = z
        self._x = x

        return self
Construct pauli from boolean array.

        Args:
            z (numpy.ndarray): boolean, z vector
            x (numpy.ndarray): boolean, x vector

        Returns:
            Pauli: self

        Raises:
            QiskitError: if z or x are None or the length of z and x are different.