a
    a'                     @   sp   d Z ddlZddlZddlZddlmZmZm	Z	m
Z
mZ ddlmZ ddlmZ g ZG dd dZdddZdS )zTrust-region optimization.    N   )_check_unknown_options_wrap_function_status_messageOptimizeResult_prepare_scalar_function)HessianUpdateStrategy)
FD_METHODSc                   @   sj   e Zd ZdZdddZdd Zedd Zed	d
 Zedd Z	dd Z
edd Zdd Zdd ZdS )BaseQuadraticSubproblemaQ  
    Base/abstract class defining the quadratic model for trust-region
    minimization. Child classes must implement the ``solve`` method.

    Values of the objective function, Jacobian and Hessian (if provided) at
    the current iterate ``x`` are evaluated on demand and then stored as
    attributes ``fun``, ``jac``, ``hess``.
    Nc                 C   sF   || _ d | _d | _d | _d | _d | _d | _|| _|| _|| _	|| _
d S N)_x_f_g_h_g_magZ_cauchy_pointZ_newton_point_fun_jac_hess_hessp)selfxfunjachesshessp r   k/Users/vegardjervell/Documents/master/model/venv/lib/python3.9/site-packages/scipy/optimize/_trustregion.py__init__   s    z BaseQuadraticSubproblem.__init__c                 C   s*   | j t| j| dt|| |  S )Ng      ?)r   npdotr   r   r   pr   r   r   __call__$   s    z BaseQuadraticSubproblem.__call__c                 C   s   | j du r| | j| _ | j S )z1Value of objective function at current iteration.N)r   r   r   r   r   r   r   r   '   s    
zBaseQuadraticSubproblem.func                 C   s   | j du r| | j| _ | j S )z=Value of Jacobian of objective function at current iteration.N)r   r   r   r#   r   r   r   r   .   s    
zBaseQuadraticSubproblem.jacc                 C   s   | j du r| | j| _ | j S )z<Value of Hessian of objective function at current iteration.N)r   r   r   r#   r   r   r   r   5   s    
zBaseQuadraticSubproblem.hessc                 C   s*   | j d ur|  | j|S t| j|S d S r   )r   r   r   r   r   r    r   r   r   r   <   s    
zBaseQuadraticSubproblem.hesspc                 C   s    | j du rtj| j| _ | j S )zAMagnitude of jacobian of objective function at current iteration.N)r   scipylinalgZnormr   r#   r   r   r   jac_magB   s    
zBaseQuadraticSubproblem.jac_magc                 C   s   t ||}dt || }t |||d  }t|| d| |  }|t|| }| d|  }	d| | }
t|	|
gS )z
        Solve the scalar quadratic equation ||z + t d|| == trust_radius.
        This is like a line-sphere intersection.
        Return the two values of t, sorted from low to high.
              )r   r   mathsqrtcopysignsorted)r   zdtrust_radiusabcZsqrt_discriminantZauxtatbr   r   r   get_boundaries_intersectionsI   s    	z4BaseQuadraticSubproblem.get_boundaries_intersectionsc                 C   s   t dd S )Nz9The solve method should be implemented by the child class)NotImplementedError)r   r0   r   r   r   solve`   s    zBaseQuadraticSubproblem.solve)NN)__name__
__module____qualname____doc__r   r"   propertyr   r   r   r   r&   r6   r8   r   r   r   r   r
      s   	




r
   r         ?     @@333333?-C6?FTc           "         sr  t | |du rtd|du r0|du r0td|du r@tdd|	  krTdk s^n td|dkrntd|dkr~td	||krtd
t| }t| ||||d  j}  j}t	|rʈ j
}n6t	|rn,|tv st|trd} fdd}ntdt||\}}|du r$t|d }d}|}|}|r<|g}||| |||}d}|j|
krz||\}}W n$ tjjjy   d}Y qY n0 ||}|| }||| |||}|j|j }|j| }|dkrd}q|| }|dk r|d9 }n|dkr|rtd| |}||	kr(|}|}|r>|t| |durV|t| |d7 }|j|
k rrd}q||krPd}qqPtd td ddf} |r|dkrt| |  ntd| |   td|j  td|  td j  td j  td j|d    t||dk||j|j j j j|d  || | d
}!|dur`|j
|!d< |rn||!d< |!S ) a  
    Minimization of scalar function of one or more variables using a
    trust-region algorithm.

    Options for the trust-region algorithm are:
        initial_trust_radius : float
            Initial trust radius.
        max_trust_radius : float
            Never propose steps that are longer than this value.
        eta : float
            Trust region related acceptance stringency for proposed steps.
        gtol : float
            Gradient norm must be less than `gtol`
            before successful termination.
        maxiter : int
            Maximum number of iterations to perform.
        disp : bool
            If True, print convergence message.
        inexact : bool
            Accuracy to solve subproblems. If True requires less nonlinear
            iterations, but more vector products. Only effective for method
            trust-krylov.

    This function is called by the `minimize` function.
    It is not supposed to be called directly.
    Nz7Jacobian is currently required for trust-region methodsz_Either the Hessian or the Hessian-vector product is currently required for trust-region methodszBA subproblem solving strategy is required for trust-region methodsr   g      ?zinvalid acceptance stringencyz%the max trust radius must be positivez)the initial trust radius must be positivez?the initial trust radius must be less than the max trust radius)r   r   argsc                    s     | |S r   )r   r   )r   r!   rB   Zsfr   r   r      s    z%_minimize_trust_region.<locals>.hessp      r'   g      ?r   successmaxiterz:A bad approximation caused failure to predict improvement.z3A linalg error occurred, such as a non-psd Hessian.z	Warning: z#         Current function value: %fz         Iterations: %dz!         Function evaluations: %dz!         Gradient evaluations: %dz          Hessian evaluations: %d)
r   rF   statusr   r   nfevZnjevnhevZnitmessager   allvecs)r   
ValueError	Exceptionr   Zasarrayflattenr   r   Zgradcallabler   r	   
isinstancer   r   lenr&   r8   r%   ZLinAlgErrorminappendcopyr   printrI   ZngevrJ   r   r   )"r   Zx0rB   r   r   r   Z
subproblemZinitial_trust_radiusZmax_trust_radiusetaZgtolrG   ZdispZ
return_allcallbackZinexactZunknown_optionsZnhesspZwarnflagr0   r   rL   mkr!   Zhits_boundaryZpredicted_valueZ
x_proposedZ
m_proposedZactual_reductionZpredicted_reductionrhoZstatus_messagesresultr   rC   r   _minimize_trust_regione   s    










r]   )r   NNNNr>   r?   r@   rA   NFFNT)r<   r*   Znumpyr   Zscipy.linalgr$   optimizer   r   r   r   r   Z'scipy.optimize._hessian_update_strategyr   Z(scipy.optimize._differentiable_functionsr	   __all__r
   r]   r   r   r   r   <module>   s   X     