potential
.. math:: Q(\xi,\lambda) = \frac{1}{2} \beta k (\xi - \lambda)^2,
+ :label: eqnawhbasic
so that for large force constants :math:`k`,
:math:`\xi \approx \lambda`. Note the use of dimensionless energies for
repeatedly with limited and localized sampling,
.. math:: \Delta F_n = -\ln \frac{W_n(\lambda) + \sum_t \omega_n(\lambda|x(t))}{W_n(\lambda) + \sum_t\rho_n(\lambda)) }.
+ :label: eqnawhsampling
Here :math:`W_n(\lambda)` is the *reference weight histogram*
representing prior sampling. The update for :math:`W(\lambda)`,
be uniform
.. math:: \rho_{\mathrm{const}}(\lambda) = \mathrm{const.}
+ :label: eqnawhuniformdist
This choice exactly flattens :math:`F(\lambda)` in user-defined
sampling interval :math:`I`. Generally,
weight histogram
.. math:: \rho_{\mathrm{Boltz,loc}}(\lambda) \propto W(\lambda),
+ :label: eqnawhweighthistogram
and the update of the weight histogram is modified (cf.
:eq:`Eq. %s <eqawhwupdate>`)
.. math:: W_{n+1}(\lambda) = W_{n}(\lambda) + s_{\beta}\sum_t \omega(\lambda | x(t)).
+ :label: eqnawhupdateweighthist
Thus, here the weight histogram equals the real history of samples, but
scaled by :math:`s_\beta`. This target distribution is called *local*
probability weights
.. math:: \rho(\lambda) = \rho_0(\lambda) w_{\mathrm{user}}(\lambda).
+ :label: eqnawhpropweigth
where :math:`w_{\mathrm{user}}(\lambda)` is provided by user data and
in principle :math:`\rho_0(\lambda)` can be any of the target