org.abora.white.spaces.cross
Class GenericCrossRegion

java.lang.Object
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  +--org.abora.white.xpp.basic.Heaper
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        +--org.abora.white.spaces.basic.XnRegion
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              +--org.abora.white.spaces.cross.CrossRegion
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                    +--org.abora.white.spaces.cross.GenericCrossRegion

public class GenericCrossRegion

extends CrossRegion

Represents a region as a two-dimensional array of crosses of subregions. Was NOT.A.TYPE but that obstructed compilation. I think this might work better if the array is lexically sorted, but I am not sure there is any meaningful way to do so. Thus there is no sorting assumed in the algorithms, although the protocol may occasionally suggest that there might be. Eventually this implementation may save space by using NULL to represent repetitions of a sub region such that fetchBoxProjection (box, dim) == NULL only if box > 0 && boxProjection (box, dim)->isEqual (boxProjection (box - 1, dim)) && (dim == 0 || fetchBoxProjection (box, dim - 1) == NULL)

Field Summary

protected int	myCount
protected PtrArray	myRegions
protected CrossSpace	mySpace

Constructor Summary

GenericCrossRegion(CrossSpace space, int count, PtrArray regions)

GenericCrossRegion(Rcvr receiver)

Method Summary

int	actualHashForEqual() To avoid overly burdensome canonicalization rules, my hash is calculated from the hash of my projections
Stepper	actualStepper(OrderSpec order) Only called if I've already said I'm enumerable in the originally stated order.
XnRegion	asSimpleRegion() Return a simple region containing all positions contained by myself.
int	boxCount()
Stepper	boxes() Essential.
XnRegion	boxProjection(int box, int dimension) A region is at a given 2D place in the array
BoxProjectionStepper	boxProjectionStepper() A stepper over all projections of all boxes in the region
BoxStepper	boxStepper() A stepper over all boxes
XnRegion	complement() Essential.
CoordinateSpace	coordinateSpace() Essential.
IntegerValue	count() How many positions do I contain? If I am not 'isFinite', then this message will BLAST.
CrossSpace	crossSpace()
ScruSet	distinctions() Break it up into a set of non-full distinctions.
static CrossRegion	empty(GenericCrossSpace space)
static CrossRegion	full(GenericCrossSpace space, PtrArray subSpaces) Only used during construction; must pass the array in explicitly since the space isnt initialized yet
boolean	hasBoxProjection(XnRegion other, int box, int dimension) Whether a region is at a given 2D place in the array.
boolean	hasMember(Position position) Do I contain this position? More than anything else, the behavior of this message is the defining characteristic of an XuRegion.
XnRegion	intersect(XnRegion region) Essential.
boolean	intersects(XnRegion other) Essential.
boolean	isBox() Whether this Region is a box, i.e.
boolean	isDistinction() Am I a distinction.
boolean	isEmpty() Every coordinate space has exactly one empty region.
boolean	isEnumerable(OrderSpec order) See comment in XuRegion::stepper.
boolean	isEqual(Heaper other) Two regions are equal iff they contain exactly the same set of positions
boolean	isFinite() Essential.
boolean	isFull() true if this is the largest possible region in this space -- the region that contains all positions in the space.
boolean	isSimple() Am I a simple region.
boolean	isSubsetOf(XnRegion other) I'm a subset of other if I don't have any positions that he doesn't.
static CrossRegion	make(CrossSpace space, int count, PtrArray regions)
void	printOn(java.io.PrintWriter oo) This should rarely be overridden.
XnRegion	projection(int index) The answer is the projection of this region into the specified dimension of the cross space
PtrArray	projections() Essential.
PtrArray	secretRegions() The array holding the regions.
void	sendSelfTo(Xmtr xmtr)
Stepper	simpleRegions(OrderSpec order) Break myself up into a finite set of non-empty simple regions which, when unionWith'ed together will yield me.
Position	theOne() Iff I contain exactly one position, return it.
XnRegion	unionWith(XnRegion region) The result has as members exactly those positions which are members of either of the original two regions.

Methods inherited from class org.abora.white.spaces.cross.CrossRegion

info, simpleUnion

Methods inherited from class org.abora.white.spaces.basic.XnRegion

chooseMany, chooseMany, chooseOne, chooseOne, delta, disjointSimpleRegions, disjointSimpleRegions, immuSet, isEnumerable, minus, simpleRegions, stepper, stepper, with, without

Methods inherited from class org.abora.white.xpp.basic.Heaper

destroy, destruct, equals, hashForEqual, printContentsOn, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

mySpace

protected CrossSpace mySpace

myCount

protected int myCount

myRegions

protected PtrArray myRegions

Constructor Detail

GenericCrossRegion

public GenericCrossRegion(CrossSpace space,
                          int count,
                          PtrArray regions)

GenericCrossRegion

public GenericCrossRegion(Rcvr receiver)

Method Detail

coordinateSpace

public CoordinateSpace coordinateSpace()

Description copied from class: XnRegion

Essential. The coordinate space in which this is a region

Specified by:

coordinateSpace in class CrossRegion

count

public IntegerValue count()

Description copied from class: XnRegion

How many positions do I contain? If I am not 'isFinite', then this message will BLAST.

Specified by:

count in class CrossRegion

projection

public XnRegion projection(int index)

Description copied from class: CrossRegion

The answer is the projection of this region into the specified dimension of the cross space

Overrides:

projection in class CrossRegion

projections

public PtrArray projections()

Description copied from class: CrossRegion

Essential. The answer is the projection of this region into each dimension of the cross space. Note that two regions which are different can have the same projections.

Specified by:

projections in class CrossRegion

theOne

public Position theOne()

Description copied from class: XnRegion

Iff I contain exactly one position, return it. Otherwise BLAST. The idea for this message is taken from the THE function of ONTIC (reference McAllester)

Overrides:

theOne in class XnRegion

crossSpace

public CrossSpace crossSpace()

boxCount

public int boxCount()

boxProjection

public XnRegion boxProjection(int box,
                              int dimension)

A region is at a given 2D place in the array

boxProjectionStepper

public BoxProjectionStepper boxProjectionStepper()

A stepper over all projections of all boxes in the region

boxStepper

public BoxStepper boxStepper()

A stepper over all boxes

hasBoxProjection

public boolean hasBoxProjection(XnRegion other,
                                int box,
                                int dimension)

Whether a region is at a given 2D place in the array. Searches forward and backward through adjacent boxes which have the same hash value

secretRegions

public PtrArray secretRegions()

The array holding the regions. DO NOT MODIFY

actualHashForEqual

public int actualHashForEqual()

Description copied from class: CrossRegion

To avoid overly burdensome canonicalization rules, my hash is calculated from the hash of my projections

Overrides:

actualHashForEqual in class CrossRegion

hasMember

public boolean hasMember(Position position)

Description copied from class: XnRegion

Do I contain this position? More than anything else, the behavior of this message is the defining characteristic of an XuRegion. All other messages (except for the simplicity characterization) should be specifiable in terms of the behavior of this message. What an XuRegion *is* (mostly) is a finite decision procedure for accepting or rejecting any given position.

Specified by:

hasMember in class CrossRegion

intersects

public boolean intersects(XnRegion other)

Description copied from class: XnRegion

Essential. tell whether it has any points in common

Overrides:

intersects in class XnRegion

isDistinction

public boolean isDistinction()

Description copied from class: XnRegion

Am I a distinction. See XuRegion class comment for implications of being a distinction.

Overrides:

isDistinction in class XnRegion

isEmpty

public boolean isEmpty()

Description copied from class: XnRegion

Every coordinate space has exactly one empty region. It is the one containing no positions. It and only it responds 'true' to this message.

Specified by:

isEmpty in class CrossRegion

isEnumerable

public boolean isEnumerable(OrderSpec order)

Description copied from class: XnRegion

See comment in XuRegion::stepper. a->stepper(os) won't BLAST iff a->isEnumerable(os)

Specified by:

isEnumerable in class CrossRegion

isEqual

public boolean isEqual(Heaper other)

Description copied from class: XnRegion

Two regions are equal iff they contain exactly the same set of positions

Specified by:

isEqual in class CrossRegion

isFinite

public boolean isFinite()

Description copied from class: XnRegion

Essential. Do I contain a finite number of positions? If I do, then the 'count' message will say how many, and I will gladly provide a stepper which will step over all of them. I.e., isFinite implies isEnumerable.

Specified by:

isFinite in class CrossRegion

isFull

public boolean isFull()

Description copied from class: XnRegion

true if this is the largest possible region in this space -- the region that contains all positions in the space. Note that in a space which has no positions (which is perfectly valid), the one XuRegion would be both empty (since it has no positions) and full (since it has all the positions in the space).

Overrides:

isFull in class XnRegion

isSimple

public boolean isSimple()

Description copied from class: XnRegion

Am I a simple region. See XuRegion class comment for implications of being simple.

Specified by:

isSimple in class CrossRegion

isSubsetOf

public boolean isSubsetOf(XnRegion other)

Description copied from class: XnRegion

I'm a subset of other if I don't have any positions that he doesn't. Note that if we are equal, then I am still a subset of him. If you want to know if I'm a strict subset, you can ask a->isSubsetOf(b) && !! a->isEqual(b)

Overrides:

isSubsetOf in class XnRegion

asSimpleRegion

public XnRegion asSimpleRegion()

Description copied from class: XnRegion

Return a simple region containing all positions contained by myself. If I am simple, then the result must be me. Otherwise, the resulting region will contain more positions than I do, but it must contain all those that I do. It would be good for the resulting simple region to not contain many more points than it needs in order to satisfy these constraints; but this is a preference, not a specification. Particular spaces may specify stronger guarantees, but as far as class XuRegion is concerned it is correct (though silly) for this message to always return the full region for the space.

Specified by:

asSimpleRegion in class CrossRegion

complement

public XnRegion complement()

Description copied from class: XnRegion

Essential. Return a region of containing exactly those positions not in this region. The complement of a distinction must be a distinction.

Specified by:

complement in class CrossRegion

intersect

public XnRegion intersect(XnRegion region)

Description copied from class: XnRegion

Essential. The intersection of two simple regions must be simple. The intersection of two distinctions must therefore be a simple region. The result has exactly those members which both the original regions have.

Specified by:

intersect in class CrossRegion

unionWith

public XnRegion unionWith(XnRegion region)

Description copied from class: XnRegion

The result has as members exactly those positions which are members of either of the original two regions. No matter how simple the two original regions are, the result may be non-simple. The only reason this is called 'unionWith' instead of 'union' is that the latter is a C++ keyword.

Specified by:

unionWith in class CrossRegion

printOn

public void printOn(java.io.PrintWriter oo)

Description copied from class: Heaper

This should rarely be overridden. In Tofu, it prints ClassName(...), where ... is either produced by printInsideOn or is ??? if printInsideOn it not overridden.

Overrides:

printOn in class Heaper

boxes

public Stepper boxes()

Description copied from class: CrossRegion

Essential. Divide this Region up into a disjoint sequence of boxes. A box is a region which is the cross of its projections.

Specified by:

boxes in class CrossRegion

distinctions

public ScruSet distinctions()

Description copied from class: XnRegion

Break it up into a set of non-full distinctions. It is an error to send this to a non-simple region. A full region will respond with the null set. Other distinctions will respond with a singleton set containing themselves, and simple regions will respond with a set of distinctions which, when intersected together, yield the original region.

Specified by:

distinctions in class CrossRegion

isBox

public boolean isBox()

Description copied from class: CrossRegion

Whether this Region is a box, i.e. is equal to the cross of its projections.

Specified by:

isBox in class CrossRegion

simpleRegions

public Stepper simpleRegions(OrderSpec order)

Description copied from class: XnRegion

Break myself up into a finite set of non-empty simple regions which, when unionWith'ed together will yield me. May be sent to any region. If I am isEmpty, I will respond with the empty stepper. Otherwise, if I am simple I will respond with a stepper producing just myself. Please only use NULL for the 'order' argument for now unless the documentation for a particular region or coordinate space says that it will deal with the 'order' argument meaningfully. When no order is specified then I may return the simple regions in any order. When the ordering functionality is implemented, then I am constrained to produce the simple regions in an order consistent with the argument's ordering of my positions. When the simple regions don't overlap, and don't surround each other in the ordering, then the meaning is clear. Otherwise, there are several plausible options for how we should specify this message.

Specified by:

simpleRegions in class CrossRegion

actualStepper

public Stepper actualStepper(OrderSpec order)

Description copied from class: XnRegion

Only called if I've already said I'm enumerable in the originally stated order. Also, if the originally stated order was NULL, I get a guaranteed non-null order. Subclasses which override 'stepper' to a method which doesn't send 'actualStepper' may override 'actualStepper' to a stub method which always BLASTs.

Specified by:

actualStepper in class CrossRegion

sendSelfTo

public void sendSelfTo(Xmtr xmtr)

Overrides:

sendSelfTo in class Heaper

empty

public static CrossRegion empty(GenericCrossSpace space)

full

public static CrossRegion full(GenericCrossSpace space,
                               PtrArray subSpaces)

Only used during construction; must pass the array in explicitly since the space isnt initialized yet

make

public static CrossRegion make(CrossSpace space,
                               int count,
                               PtrArray regions)