Limits to use for the independent variable whenever
        creating a linespace, plot, etc.

        Defaults to `(-x, x)` where `x` is the largest absolute value
        of the data corresponding to the independent variable.
        If no such values are negative, defaults to `(0, x)` instead.

def limits(self):
        """
        Limits to use for the independent variable whenever
        creating a linespace, plot, etc.

        Defaults to `(-x, x)` where `x` is the largest absolute value
        of the data corresponding to the independent variable.
        If no such values are negative, defaults to `(0, x)` instead.
        """
        if not hasattr(self, '_limits'):
            xmax = max(abs(self.data.array[0]))
            xmin = min(self.data.array[0])

            x_error = self.data.error[0]
            if isinstance(x_error, numpy.ndarray):
                if x_error.ndim == 0: xmax = xmax + x_error

            if xmin < 0:
                self._limits = (-xmax, xmax)
            else:
                self._limits = (0, xmax)

        return self._limits