Package ML :: Package InfoTheory :: Module BitRank

Module BitRank

Functionality for ranking bits using info gains

**Definitions used in this module**

   - *sequence*: an object capable of containing other objects which supports
     __getitem__() and __len__().  Examples of these include lists, tuples, and
     Numeric arrays.

   - *IntVector*: an object containing integers which supports __getitem__() and
      __len__(). Examples include lists, tuples, Numeric Arrays, and BitVects.


**NOTE**: Neither *sequences* nor *IntVectors* need to support item assignment.
  It is perfectly acceptable for them to be read-only, so long as they are
  random-access.

Functions

[hide private]

FormCounts(bitVects, actVals, whichBit, nPossibleActs, nPossibleBitVals=2)
generates the counts matrix for a particular bit **Arguments** - bitVects: a *sequence* containing *IntVectors* - actVals: a *sequence* - whichBit: an integer, the bit number to use.

source code

CalcInfoGains(bitVects, actVals, nPossibleActs, nPossibleBitVals=2)
Calculates the information gain for a set of points and activity values **Arguments** - bitVects: a *sequence* containing *IntVectors* - actVals: a *sequence* - nPossibleActs: the (integer) number of possible activity values.

source code

RankBits(bitVects, actVals, nPossibleBitVals=2, metricFunc=<function CalcInfoGains at 0x9f7a2cc>)
Rank a set of bits according to a metric function **Arguments** - bitVects: a *sequence* containing *IntVectors* - actVals: a *sequence* - nPossibleBitVals: (optional) if specified, this integer provides the maximum value attainable by the (increasingly inaccurately named) bits in _bitVects_.

source code

AnalyzeSparseVects(bitVects, actVals)
#DOC ...

source code

SparseRankBits(bitVects, actVals, metricFunc=<function AnalyzeSparseVects at 0x9f7a224>)
Rank a set of bits according to a metric function **Arguments** - bitVects: a *sequence* containing SBVs - actVals: a *sequence* - metricFunc: (optional) the metric function to be used.

source code

Variables

[hide private]

Complex0 = 'F'

Complex16 = 'F'

Complex32 = 'F'

Complex64 = 'D'

Complex8 = 'F'

Float0 = 'f'

Float16 = 'f'

Float32 = 'f'

Float64 = 'd'

Float8 = 'f'

Int0 = '1'

Int16 = 's'

Int32 = 'i'

Int8 = '1'

absolute = <ufunc 'absolute'>

add = <ufunc 'add'>

arccos = <ufunc 'arccos'>

arccosh = <ufunc 'arccosh'>

arcsin = <ufunc 'arcsin'>

arcsinh = <ufunc 'arcsinh'>

arctan = <ufunc 'arctan'>

arctan2 = <ufunc 'arctan2'>

arctanh = <ufunc 'arctanh'>

bitwise_and = <ufunc 'bitwise_and'>

bitwise_or = <ufunc 'bitwise_or'>

bitwise_xor = <ufunc 'bitwise_xor'>

ceil = <ufunc 'ceil'>

conjugate = <ufunc 'conjugate'>

cos = <ufunc 'cos'>

cosh = <ufunc 'cosh'>

divide = <ufunc 'divide'>

divide_safe = <ufunc 'divide_safe'>

e = 2.71828182846

equal = <ufunc 'equal'>

exp = <ufunc 'exp'>

fabs = <ufunc 'fabs'>

floor = <ufunc 'floor'>

floor_divide = <ufunc 'floor_divide'>

fmod = <ufunc 'fmod'>

greater = <ufunc 'greater'>

greater_equal = <ufunc 'greater_equal'>

hypot = <ufunc 'hypot'>

invert = <ufunc 'invert'>

left_shift = <ufunc 'left_shift'>

less = <ufunc 'less'>

less_equal = <ufunc 'less_equal'>

log = <ufunc 'log'>

log10 = <ufunc 'log10'>

logical_and = <ufunc 'logical_and'>

logical_not = <ufunc 'logical_not'>

logical_or = <ufunc 'logical_or'>

logical_xor = <ufunc 'logical_xor'>

maximum = <ufunc 'maximum'>

minimum = <ufunc 'minimum'>

multiply = <ufunc 'multiply'>

negative = <ufunc 'negative'>

not_equal = <ufunc 'not_equal'>

pi = 3.14159265359

power = <ufunc 'power'>

remainder = <ufunc 'remainder'>

right_shift = <ufunc 'right_shift'>

sin = <ufunc 'sin'>

sinh = <ufunc 'sinh'>

sqrt = <ufunc 'sqrt'>

subtract = <ufunc 'subtract'>

tan = <ufunc 'tan'>

tanh = <ufunc 'tanh'>

true_divide = <ufunc 'true_divide'>

Function Details

[hide private]

FormCounts(bitVects, actVals, whichBit, nPossibleActs, nPossibleBitVals=2)

source code

generates the counts matrix for a particular bit

**Arguments**

  - bitVects: a *sequence* containing *IntVectors*

  - actVals: a *sequence*

  - whichBit: an integer, the bit number to use.

  - nPossibleActs: the (integer) number of possible activity values.

  - nPossibleBitVals: (optional) if specified, this integer provides the maximum
    value attainable by the (increasingly inaccurately named) bits in _bitVects_.

**Returns**

  a Numeric array with the counts

**Notes**

  This is really intended for internal use.

CalcInfoGains(bitVects, actVals, nPossibleActs, nPossibleBitVals=2)

source code

Calculates the information gain for a set of points and activity values

**Arguments**

  - bitVects: a *sequence* containing *IntVectors*

  - actVals: a *sequence*

  - nPossibleActs: the (integer) number of possible activity values.

  - nPossibleBitVals: (optional) if specified, this integer provides the maximum
    value attainable by the (increasingly inaccurately named) bits in _bitVects_.

 **Returns**   

   a list of floats

RankBits(bitVects, actVals, nPossibleBitVals=2, metricFunc=<function CalcInfoGains at 0x9f7a2cc>)

source code

Rank a set of bits according to a metric function

**Arguments**

  - bitVects: a *sequence* containing *IntVectors*

  - actVals: a *sequence*

  - nPossibleBitVals: (optional) if specified, this integer provides the maximum
    value attainable by the (increasingly inaccurately named) bits in _bitVects_.

  - metricFunc: (optional) the metric function to be used.  See _CalcInfoGains()_
    for a description of the signature of this function.

 **Returns**

   A 2-tuple containing:

     - the relative order of the bits (a list of ints)

     - the metric calculated for each bit (a list of floats)

AnalyzeSparseVects(bitVects, actVals)

source code

#DOC 

**Arguments**

  - bitVects: a *sequence* containing SBVs

  - actVals: a *sequence*

 **Returns**   

   a list of floats

 **Notes**

    - these need to be bit vects and binary activities

SparseRankBits(bitVects, actVals, metricFunc=<function AnalyzeSparseVects at 0x9f7a224>)

source code

Rank a set of bits according to a metric function

**Arguments**

  - bitVects: a *sequence* containing SBVs

  - actVals: a *sequence*

  - metricFunc: (optional) the metric function to be used.  See _SparseCalcInfoGains()_
    for a description of the signature of this function.

 **Returns**

   A 2-tuple containing:

     - the relative order of the bits (a list of ints)

     - the metric calculated for each bit (a list of floats)

  **Notes**

    - these need to be bit vects and binary activities