.. index:: rsamplers.apt.apt
.. _rsamplers_apt:

  rsamplers.apt is the constructor for the Adaptive Parallel
  tempering algorithm following :cite:`MiasojedowEtAl2013`
 
  The syntax is ::
 
  	obj = rsamplers.apt(target,x0,lb,ub)
  	obj = rsamplers.apt(target,x0,lb,ub,opts)
  	obj = rsamplers.apt(target,x0,lb,ub,opts,constraints)
 
  INPUTS :
 
    - \*target\* : objective to MAXIMIZE
    - \*x0\* : vector of initial conditions
    - \*lb\* : lower bound
    - \*ub\* : upper bound
    - \*opts\* : options for the class. These include the properties
      from the superclass **rsamplers.rwmh** as well as the specific
      properties of the apt algorithm that can be found in the
      properties list below.
    - \*constraints\* (optional):  - Matrix (n_constraints x 2)
      where each row [a, b] enforces x(a) <= x(b)
 
  OUTPUT :
 
    - obj : object of class rsamplers.apt
 
  OWN PROPERTIES AND DEFAULT VALUES:
 
    - \*H\* = 12 : Number of tempering stages
    - \*alpha\* = .234 : target acceptance rate
    - \*alpha_swap\* = .234 :	target acceptance rate for swaps
    - \*rwm_fixed_p\* = 0	: prob of drawing from a fixed initial proposal
    - \*rwm_exp\* = 0.6 :	Exponent of random-walk adaptation step size
    - \*sw_exp_rm\* = 0.6	: Exp. of temperature adaptation step size
    - \*ram_adapt\* = false : Use the robust AM adaptation
    - \*separate_shape_adaptation\* = true :separate covariance for each temperature
    - \*fixed_temperatures\* = false : fixed temperatures
 
  INHERITED PROPERTIES : properties from rsamplers.rwmh
 
  .. seealso:: rsamplers.rwmh, rsamplers.imh, rsamplers.rsampler