Home       Trees       Indices       Help   
PyMVPA: Python MultiVariate Pattern Analysis
Package mvpa :: Package mappers :: Module base :: Class ChainMapper
[hide private]
[frames] | no frames]

Class ChainMapper

source code

Meta mapper that embedded a chain of other mappers.

Each mapper in the chain is called successively to perform forward or reverse mapping.

In its current implementation the ChainMapper treats all but the last mapper as simple pre-processing (in forward()) or post-processing (in reverse()) steps. All other capabilities, e.g. training and neighbor metrics are provided by or affect only the last mapper in the chain.

With respect to neighbor metrics this means that they are determined based on the input space of the last mapper in the chain and not on the input dataspace of the ChainMapper as a whole

Instance Methods [hide private]
 
__init__(self, mappers, **kwargs)
:Parameters: mappers: list of Mapper instances **kwargs All additional arguments are passed to the base-class constructor.		 source code
 
forward(self, data)
Calls all mappers in the chain successively.		 source code
 
reverse(self, data)
Calls all mappers in the chain successively, in reversed order.		 source code
 
train(self, dataset)
Trains the *last* mapper in the chain.		 source code
 
getInSize(self)
Returns the size of the entity in input space		 source code
 
getOutSize(self)
Returns the size of the entity in output space		 source code
 
selectOut(self, outIds)
Remove some elements from the last mapper in the chain.		 source code
 
getNeighbor(self, outId, *args, **kwargs)
Get the ids of the neighbors of a single feature in output dataspace.		 source code
 
__repr__(self)
repr(x)		 source code

Inherited from Mapper: __call__, getInId, getMetric, getNeighborIn, getNeighbors, isValidInId, isValidOutId, setMetric

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __setattr__, __sizeof__, __str__, __subclasshook__

Class Variables [hide private]

Inherited from Mapper: metric, nfeatures

Properties [hide private]

Inherited from object: __class__

Method Details [hide private]

__init__(self, mappers, **kwargs)
(Constructor)

source code  

:Parameters:
  mappers: list of Mapper instances
  **kwargs
    All additional arguments are passed to the base-class constructor.
Parameters:
  • metric - Optional metric
Overrides: object.__init__

forward(self, data)

source code 
Calls all mappers in the chain successively.
Overrides: Mapper.forward

reverse(self, data)

source code 
Calls all mappers in the chain successively, in reversed order.
Overrides: Mapper.reverse

train(self, dataset)

source code  
Trains the *last* mapper in the chain.

:Parameter:
  dataset: :class:`~mvpa.datasets.base.Dataset` or subclass
    A dataset with the number of features matching the `outSize` of the
    last mapper in the chain (which is identical to the one of the
    `ChainMapper` itself).
Overrides: Mapper.train

getInSize(self)

source code 
Returns the size of the entity in input space
Overrides: Mapper.getInSize

getOutSize(self)

source code 
Returns the size of the entity in output space
Overrides: Mapper.getOutSize

selectOut(self, outIds)

source code 
Remove some elements from the last mapper in the chain.
Parameters:
  • outIds, sequence - Subset of ids of the current feature in OUT space to keep.
Overrides: Mapper.selectOut

getNeighbor(self, outId, *args, **kwargs)

source code 

Get the ids of the neighbors of a single feature in output dataspace.

The neighbors are determined based on the input space of the last mapper in the chain and not on the input dataspace of the ChainMapper as a whole!

Returns a list of outIds

Overrides: Mapper.getNeighbor

Parameters:

outId: int
Single id of a feature in output space, whos neighbors should be determined.
*args, **kwargs
Additional arguments are passed to the metric of the embedded mapper, that is responsible for the corresponding feature.

__repr__(self)
(Representation operator)

source code 
repr(x)
Overrides: object.__repr__
(inherited documentation)

   Home       Trees       Indices       Help   
PyMVPA: Python MultiVariate Pattern Analysis
Generated by Epydoc 3.0.1 on Mon Apr 23 23:09:27 2012 http://epydoc.sourceforge.net