ó
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 e Z Wn! e k
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 d „  Z d S(
   sF  
This module provides code for doing logistic regressions.


Classes:
LogisticRegression    Holds information for a LogisticRegression classifier.


Functions:
train        Train a new classifier.
calculate    Calculate the probabilities of each class, given an observation.
classify     Classify an observation into a class.
iÿÿÿÿ(   t   SetNt   LogisticRegressionc           B   s   e  Z d  Z d „  Z RS(   s‘   Holds information necessary to do logistic regression
    classification.

    Members:
    beta    List of the weights for each dimension.

    c         C   s   g  |  _  d S(   s   LogisticRegression()N(   t   beta(   t   self(    (    s‰   /oak/stanford/groups/akundaje/marinovg/programs/biopython-1.50.tar.gz/biopython-1.50/build/lib.linux-x86_64-2.7/Bio/LogisticRegression.pyt   __init__$   s    (   t   __name__t
   __module__t   __doc__R   (    (    (    s‰   /oak/stanford/groups/akundaje/marinovg/programs/biopython-1.50.tar.gz/biopython-1.50/build/lib.linux-x86_64-2.7/Bio/LogisticRegression.pyR      s   c         C   sæ  t  |  ƒ t  | ƒ k r' t d ƒ ‚ n  t | ƒ } | t d d g ƒ k rZ t d ƒ ‚ n  | d k ro d } n  t  |  ƒ t  |  d ƒ d } } | d k s¨ | d k r· t d ƒ ‚ n  t j | | f | ƒ } |  | d d … d d … f <t j | ƒ } t j | | ƒ }	 t j | | ƒ }
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 |
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 n  | d k	 rt j | | ƒ | k rPn  | |
 } } | d 7} t j | ƒ | } t j
 | |	 | ƒ } t j
 t j
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 ƒ d k r­| | } n  |
 | }
 qCWt d ƒ ‚ t ƒ  } t t |
 ƒ | _ | S(   s”  train(xs, ys[, update_fn]) -> LogisticRegression
    
    Train a logistic regression classifier on a training set.  xs is a
    list of observations and ys is a list of the class assignments,
    which should be 0 or 1.  xs and ys should contain the same number
    of elements.  update_fn is an optional callback function that
    takes as parameters that iteration number and log likelihood.
    
    s$   xs and ys should be the same length.i    i   s   Classes should be 0's and 1'st   ds.   No observations or observation of 0 dimension.Niô  g{®Gáz„?g      ð?g       @gü©ñÒMbP?s   Didn't converge.(   t   lent
   ValueErrort   sett   Nonet   numpyt   onest	   transposet   asarrayt   zerost   expt   dott   logt   sumt   fabst   identityt   linalgt   solvet   RuntimeErrorR   t   mapt   floatR   (   t   xst   yst	   update_fnt   typecodet   classest   Nt   ndimst   Xt   Xtt   yR   t   MAX_ITERATIONSt   CONVERGE_THRESHOLDt   stepsizet   itert   old_betat   old_llikt   ebetaXt   pt   logpt   llikt   Wt   Xtypt   XtWXt   deltat   lr(    (    s‰   /oak/stanford/groups/akundaje/marinovg/programs/biopython-1.50.tar.gz/biopython-1.50/build/lib.linux-x86_64-2.7/Bio/LogisticRegression.pyt   train(   sZ    
	!
,
	%
	c         C   sP   t  j d g | ƒ } t  j t  j |  j | ƒ ƒ } | d | } d | | g S(   sß   calculate(lr, x) -> list of probabilities

    Calculate the probability for each class.  lr is a
    LogisticRegression object.  x is the observed data.  Returns a
    list of the probability that it fits each class.

    g      ð?i   (   R   R   R   R   R   (   R5   t   xR-   R.   (    (    s‰   /oak/stanford/groups/akundaje/marinovg/programs/biopython-1.50.tar.gz/biopython-1.50/build/lib.linux-x86_64-2.7/Bio/LogisticRegression.pyt	   calculatev   s    	c         C   s+   t  |  | ƒ } | d | d k r' d Sd S(   sJ   classify(lr, x) -> 1 or 0

    Classify an observation into a class.

    i    i   (   R8   (   R5   R7   t   probs(    (    s‰   /oak/stanford/groups/akundaje/marinovg/programs/biopython-1.50.tar.gz/biopython-1.50/build/lib.linux-x86_64-2.7/Bio/LogisticRegression.pyt   classify…   s    (    (   R   R   t	   NameErrort   setsR    R   t   numpy.linalgR   R   R6   R8   R:   (    (    (    s‰   /oak/stanford/groups/akundaje/marinovg/programs/biopython-1.50.tar.gz/biopython-1.50/build/lib.linux-x86_64-2.7/Bio/LogisticRegression.pyt   <module>   s   
N	