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java.lang.Object hu.birot.OTKit.otBuildingBlocks.Topology
public class Topology
Realizes the neighborhood structure (a.k.a. topology) on the candidate set. It defines a relation among the candidates originating from the same underlying form.
Candidates Candidate(uf1,sf1) and Candidate(uf2,sf2) can be neighbors of each other only if uf1 and uf2 are the same (are equal, at least for the equals method). In such a case, whether the two candidates are neighbors usually depends on sf1 and sf2 only, even though this restriction needs not be always met. Another frequently met requirement is that neighborhood be a symmetric and irreflexive relation.
To create a Topology, you can either employ a MapForm, or implement the methods yourself. The second is often much more efficient. Additionally, if the topology also depends on the underlying form, you cannot use a MapForm, since the MapForm defines a mapping exclusively on the surface forms.
In both cases you must be aware of which methods you will use. If you use performance.randomWalks.randomWalk, you will only need Topology.rndNeighborOf. If, however, you use performance.randomWalks.gradientWalk or performance.randomWalks.gradientWalkrnd, then you will need Topology.allNeighborsOf. That is, depending on the type of random walk you need the Topology for, it is sufficient to override either method Topology.allNeighborsOf or method Topology.rndNeighborOf. Similarly, if you base your Topology on a MapForm, then it is sufficient to override (implement) the corresponding methods of that MapForm.
A probably frequently asked question will be what the difference
between the Topology and the underlying MapForm is. The answer is that although
both have the same methods (maybe named differently), they do not realize
a map between the same types of objects. A MapForm m
is about mapping a (surface)
Form to a set of (surface) Forms, whereas the corresponding Topology(m)
maps candidates to a set of (neighboring) candidates. (Additionally, a Gen
maps an underlying form to a set of candidates.) True, the set of neighboring
candidates will share their underlying form with the argument of the topology, whereas
looking at the surface forms only will reflect m
.
MapForm
Field Summary  

java.lang.String 
name
An optional nickname of the topology. 
Constructor Summary  

Topology()
Construct a new Topology with an empty map. 

Topology(MapForm m)
Construct a new Topology employing the MapForm m . 
Method Summary  

java.util.Vector<Candidate> 
allNeighborsOf(Candidate c)
Returns a vector of all the neighbors of candidate c . 
Candidate 
firstNeighborOf(Candidate c)
Returns the first candidate among the neighbors of candidate c . 
Candidate 
nextNeighborOf(Candidate c,
Candidate c0)
Returns the next neighbor among the neighbors of candidate c ,
the one following candidate c0 . 
Candidate 
rndNeighborOf(Candidate c,
double rnd)
Return a random neighbor of c . 
Methods inherited from class java.lang.Object 

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait 
Field Detail 

public java.lang.String name
Constructor Detail 

public Topology()
Topology
with an empty map. Can be used for instance if you
override the methods yourself.
public Topology(MapForm m)
Construct a new Topology
employing the MapForm m
.
The set of neighboring candidates of the Candidate c
will be the candidates c'
such that: c.uf == c'.uf
, and
c'.sf
is in the set to which c.sf
is mapped by m
.
For instance, Topology.firstNeighborOf(c)
is
Candidate(c.uf, m.first(c.sf))
.
m
 MapForm that contains the mapping from underlying forms to surface forms.MapForm
Method Detail 

public Candidate rndNeighborOf(Candidate c, double rnd)
Return a random neighbor of c
.
If c.sf
is not in the domain of Topology.map
, then
Candidate(c.uf, MapForm.NoMapping)
is returned.
If rnd
is too high (greater than 1), then
Candidate(c.uf, MapForm.rndTooHigh)
is returned.
If rnd
is less than 0, then the result is the same as
if rnd
were equal to 0.
c
 Candidate, the neighbor of which is returned by the method.rnd
 A random value defining which neighbor to be returned.
rnd
)
neighboring candidate c
.MapForm.random(Form, double)
,
MapForm.NoMapping
,
MapForm.RndTooHigh
public Candidate firstNeighborOf(Candidate c)
Returns the first candidate among the neighbors of candidate c
.
If c.sf
is not in the domain of Topology.map
, then
Candidate(c.uf, MapForm.NoMapping)
is returned.
c
 Candidate whose first neighbor is returned.
c
.MapForm.first(Form)
,
MapForm.NoMapping
public Candidate nextNeighborOf(Candidate c, Candidate c0)
Returns the next neighbor among the neighbors of candidate c
,
the one following candidate c0
.
If c.uf
is not equal to c0.uf
(as defined by the method
Form.equals
), then Candidate(Form(), MapForm.NotInRange)
is
returned.
Otherwise, if c0
is the last candidate among the neighbors of c
,
then the method returns a Candidate whose surface form contains is
MapForm.NoMoreForm
("ERROR: no more forms.").
If c0
is not a neighbor of c
(i.e., if c.sf
is not
mapped to c0.sf
by Topology.map
), although they share equal
underlying forms, then Candidate(c.uf, MapForm.NotInRange)
is returned.
Finally, you are returned Candidate(c.uf, MapForm.NoMapping)
,
if c.sf
is not in the domain of Topology.map
.
c
 Candidate among whose neighbors the next one is searched for.c0
 Previous neighbor of candidate c
.
c
that follows candidate c1
.MapForm.next(hu.birot.OTKit.dataType.Form, hu.birot.OTKit.dataType.Form)
,
MapForm.NoMoreForm
,
MapForm.NoMapping
,
MapForm.NotInRange
public java.util.Vector<Candidate> allNeighborsOf(Candidate c)
Returns a vector of all the neighbors of candidate c
.
They share the same underlying form: Form c.uf
.
Their surface forms come from Topology.map.all(c.sf)
, which is
the set of the (surface) forms to which c.sf
is mapped by the map
realizing the topology.
If this set is infinite, then the vector returned contains the single candidate
Candidate(c.uf, MapForm.InfiniteSet)
. Similarly, a vector with the single
Candidate(c.uf, MapForm.NoMapping)
is returned, if Topology.map
has no mapping for c
.
c
 Candidates whose neighbors are to be listed.
c
.MapForm.all(hu.birot.OTKit.dataType.Form)
,
MapForm.InfiniteSet
,
MapForm.NoMapping


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