def evals(self):
        """
        The eigenvalues of the parameter space.
        This is a Dictionary of numpy.array
        Each entry in the dictionary corresponds to the different frequency
        ranges described in vary_fmax. If vary_fmax = False, the only entry
        will be f_upper, this corresponds to integrals in [f_low,f_upper). This
        entry is always present. Each other entry will use floats as keys to
        the dictionary. These floats give the upper frequency cutoff when it is
        varying.
        Each numpy.array contains the eigenvalues which, with the eigenvectors
        in evecs, are needed to rotate the
        coordinate system to one in which the metric is the identity matrix.
        """
        if self._evals is None:
            errMsg = "The metric eigenvalues have not been set in the "
            errMsg += "metricParameters instance."
            raise ValueError(errMsg)
        return self._evals
The eigenvalues of the parameter space.
        This is a Dictionary of numpy.array
        Each entry in the dictionary corresponds to the different frequency
        ranges described in vary_fmax. If vary_fmax = False, the only entry
        will be f_upper, this corresponds to integrals in [f_low,f_upper). This
        entry is always present. Each other entry will use floats as keys to
        the dictionary. These floats give the upper frequency cutoff when it is
        varying.
        Each numpy.array contains the eigenvalues which, with the eigenvectors
        in evecs, are needed to rotate the
        coordinate system to one in which the metric is the identity matrix.