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 G dd„ deƒZddd„Zddd„Zddd„Zdd„ Zdd„ ZdS )z,
Spectral Algorithm for Nonlinear Equations
é    N)ÚOptimizeResult)Ú_check_unknown_optionsé   )Ú_nonmonotone_line_search_cruzÚ_nonmonotone_line_search_chengc                   @   s   e Zd ZdS )Ú_NoConvergenceN)Ú__name__Ú
__module__Ú__qualname__© r   r   úU/var/www/website-v5/atlas_env/lib/python3.8/site-packages/scipy/optimize/_spectral.pyr      s   r   r   ç:Œ0âŽyE>çYóøÂn¥éè  Fé
   ç»½×Ùß|Û=ç      ð?Úcruzc           *   	      sB  t |ƒ |dkrtd|f ƒ‚d‰|
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|||ˆ||| d�\}!}"}#}$}}W n tk
�rº   Y �qY nX |"| }%|$| }&t |%|%¡t |%|&¡ }|"}|$}|#‰|dk�r| |#¡ |d7 }q®t|||d�}'t||ƒ}(t|'|||(|d |d�})|)S )a›  
    Solve nonlinear equation with the DF-SANE method

    Options
    -------
    ftol : float, optional
        Relative norm tolerance.
    fatol : float, optional
        Absolute norm tolerance.
        Algorithm terminates when ``||func(x)|| < fatol + ftol ||func(x_0)||``.
    fnorm : callable, optional
        Norm to use in the convergence check. If None, 2-norm is used.
    maxfev : int, optional
        Maximum number of function evaluations.
    disp : bool, optional
        Whether to print convergence process to stdout.
    eta_strategy : callable, optional
        Choice of the ``eta_k`` parameter, which gives slack for growth
        of ``||F||**2``.  Called as ``eta_k = eta_strategy(k, x, F)`` with
        `k` the iteration number, `x` the current iterate and `F` the current
        residual. Should satisfy ``eta_k > 0`` and ``sum(eta, k=0..inf) < inf``.
        Default: ``||F||**2 / (1 + k)**2``.
    sigma_eps : float, optional
        The spectral coefficient is constrained to ``sigma_eps < sigma < 1/sigma_eps``.
        Default: 1e-10
    sigma_0 : float, optional
        Initial spectral coefficient.
        Default: 1.0
    M : int, optional
        Number of iterates to include in the nonmonotonic line search.
        Default: 10
    line_search : {'cruz', 'cheng'}
        Type of line search to employ. 'cruz' is the original one defined in
        [Martinez & Raydan. Math. Comp. 75, 1429 (2006)], 'cheng' is
        a modified search defined in [Cheng & Li. IMA J. Numer. Anal. 29, 814 (2009)].
        Default: 'cruz'

    References
    ----------
    .. [1] "Spectral residual method without gradient information for solving
           large-scale nonlinear systems of equations." W. La Cruz,
           J.M. Martinez, M. Raydan. Math. Comp. **75**, 1429 (2006).
    .. [2] W. La Cruz, Opt. Meth. Software, 29, 24 (2014).
    .. [3] W. Cheng, D.-H. Li. IMA J. Numer. Anal. **29**, 814 (2009).

    )Úchengr   z"Invalid value %r for 'line_search'é   Nc                    s   ˆ d|  d  S )Nr   r   r   )ÚkÚxÚF)Úf_0r   r   Úeta_strategyJ   s    z#_root_df_sane.<locals>.eta_strategyc                    s   ˆ dˆ  S )Nr   r   ©r   )Úf_kÚnexpr   r   ÚfnormO   s    z_root_df_sane.<locals>.fnormc                    s   t j | ¡ˆ  S )N)ÚnpÚlinalgÚnormr   )r   r   r   ÚfmeritS   s    z_root_df_sane.<locals>.fmeritr   r   Fz&too many function evaluations requiredziter %d: ||F|| = %g, sigma = %gzsuccessful convergenceTr   r   )Úetar   )Úshape)r   ÚsuccessÚmessageÚfunÚnfevÚnit)r   Ú
ValueErrorÚ
_wrap_funcÚcollectionsÚdequeÚprintÚabsr   Úsignr   r   r   ÚvdotÚappendÚ_wrap_resultr   )*ÚfuncÚx0ÚargsÚftolÚfatolÚmaxfevr   ÚcallbackÚdispÚMr   Z	sigma_epsZsigma_0Úline_searchÚunknown_optionsr"   r(   ÚfÚx_kÚx_shapeZF_kÚ
is_complexr   Zsigma_kZF_0_normÚprev_fsÚQÚCÚ	convergedr&   ZF_k_normÚdr#   ÚalphaÚxpÚfpÚFpZs_kZy_kr   r   Úresultr   )r   r   r   r   Ú_root_df_sane   sx    1



&



  þrM   c           	         s¢   t  |¡}|j‰t  ˆ|fˆ žŽ ¡ ¡ }t  |¡p:t  |¡}| ¡ }dˆd< |rx‡ ‡‡‡‡‡fdd„}t|ƒ}t|ƒ}n‡ ‡‡‡‡‡fdd„}||ˆˆ|ƒ||fS )a¬  
    Wrap a function and an initial value so that (i) complex values
    are wrapped to reals, and (ii) value for a merit function
    fmerit(x, f) is computed at the same time, (iii) iteration count
    is maintained and an exception is raised if it is exceeded.

    Parameters
    ----------
    func : callable
        Function to wrap
    x0 : ndarray
        Initial value
    fmerit : callable
        Merit function fmerit(f) for computing merit value from residual.
    nfev_list : list
        List to store number of evaluations in. Should be [0] in the beginning.
    maxfev : int
        Maximum number of evaluations before _NoConvergence is raised.
    args : tuple
        Extra arguments to func

    Returns
    -------
    wrap_func : callable
        Wrapped function, to be called as
        ``F, fp = wrap_func(x0)``
    x0_wrap : ndarray of float
        Wrapped initial value; raveled to 1-D and complex
        values mapped to reals.
    x0_shape : tuple
        Shape of the initial value array
    f : float
        Merit function at F
    F : ndarray of float
        Residual at x0_wrap
    is_complex : bool
        Whether complex values were mapped to reals

    r   r   c                    s`   ˆd ˆkrt ƒ ‚ˆd  d7  < t| ƒ ˆ¡}t ˆ|fˆ žŽ ¡ ¡ }t|ƒ}ˆ|ƒ}||fS ©Nr   r   )r   Ú_real2complexÚreshaper   ÚasarrayÚravelÚ_complex2real)r   ÚzÚvr   r?   ©r6   r"   r4   r9   Ú	nfev_listZx0_shaper   r   Ú	wrap_funcÖ   s    z_wrap_func.<locals>.wrap_funcc                    sT   ˆd ˆkrt ƒ ‚ˆd  d7  < |  ˆ¡} t ˆ| fˆ žŽ ¡ ¡ }ˆ|ƒ}||fS rN   )r   rP   r   rQ   rR   )r   r   r?   rV   r   r   rX   ã   s    
)r   rQ   r$   rR   ÚiscomplexobjrS   )	r4   r5   r"   rW   r9   r6   r   rB   rX   r   rV   r   r+   ¥   s    (


	r+   c                 C   s(   |rt | ƒ}n| }|dk	r$| |¡}|S )zA
    Convert from real to complex and reshape result arrays.
    N)rO   rP   )rL   rB   r$   rT   r   r   r   r3   ï   s    

r3   c                 C   s   t j| td� t j¡S ©N)Údtype)r   ÚascontiguousarrayÚfloatÚviewÚ
complex128)r   r   r   r   rO   ü   s    rO   c                 C   s   t j| td� t j¡S rZ   )r   r\   Úcomplexr^   Úfloat64)rT   r   r   r   rS      s    rS   )r   r   r   r   NNFr   Nr   r   r   )r   )N)Ú__doc__r,   Únumpyr   Úscipy.optimizer   Zscipy.optimize._optimizer   Ú_linesearchr   r   Ú	Exceptionr   rM   r+   r3   rO   rS   r   r   r   r   Ú<module>   s*                  þ
 
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