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Regina 7.0 Calculation Engine
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A structure used to track equivalence classes of pentachoron triangles as the gluing permutation set is constructed. More...
#include <census/gluingpermsearcher4.h>
Public Member Functions | |
| PentTriangleState () | |
| Constructor for a standalone pentachoron triangle in an equivalence class all of its own. More... | |
| void | dumpData (std::ostream &out) const |
| Dumps all internal data in a plain text format to the given output stream. More... | |
| bool | readData (std::istream &in, unsigned long nStates) |
| Fills this state with data read from the given input stream. More... | |
| PentTriangleState (const PentTriangleState &)=delete | |
| PentTriangleState & | operator= (const PentTriangleState &)=delete |
Public Attributes | |
| int | parent |
| The index of the parent object in the current tree, or -1 if this object is the root of the tree. More... | |
| unsigned | rank |
| The depth of the subtree beneath this object (where a leaf node has depth zero). More... | |
| unsigned | size |
| The total number of objects in the subtree descending from this object (where this object is counted also). More... | |
| bool | bounded |
| Does this equivalence class of pentachoron triangles represent a boundary triangle? More... | |
| Perm< 3 > | twistUp |
| The vertices of each pentachoron triangle can be labelled (0,1,2) by running through the underlying pentachoron vertices from smallest index to largest index. More... | |
| bool | hadEqualRank |
| Did this tree have rank equal to its parent immediately before it was grafted beneath its parent? This information is used to maintain the ranks correctly when grafting operations are undone. More... | |
A structure used to track equivalence classes of pentachoron triangles as the gluing permutation set is constructed.
Two triangles are considered equivalent if they are identified within the 4-manifold triangulation.
Pentachoron triangles are indexed linearly by pentachoron and then triangle number. Specifically, triangle f (0..9) of pentachoron p (0..nPents-1) has index 10p+f.
Each equivalence class of triangles corresponds to a tree of PentTriangleState objects, arranged to form a modified union-find structure.
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inline |
Constructor for a standalone pentachoron triangle in an equivalence class all of its own.
| void regina::GluingPermSearcher< 4 >::PentTriangleState::dumpData | ( | std::ostream & | out | ) | const |
Dumps all internal data in a plain text format to the given output stream.
This state can be recreated from this text data by calling readData().
This routine may be useful for transferring objects from one processor to another.
| out | the output stream to which the data should be written. |
| bool regina::GluingPermSearcher< 4 >::PentTriangleState::readData | ( | std::istream & | in, |
| unsigned long | nStates | ||
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Fills this state with data read from the given input stream.
This routine reads data in the format written by dumpData().
This routine does test for bad input data, but it does not test for end-of-file.
| in | the input stream from which to read. |
| nStates | the total number of triangle states under consideration (this must be ten times the number of pentachora). |
false if any errors were encountered during reading, or true otherwise. | bool regina::GluingPermSearcher< 4 >::PentTriangleState::bounded |
Does this equivalence class of pentachoron triangles represent a boundary triangle?
If this equivalence class describes a complete loop of pentachoron triangles then the value of bounded is false. If this equivalence class describes a string of pentachoron triangles with two endpoints, the value of bounded is true. Here we treat any facet whose gluing permutation has not yet been decided as a boundary facet.
This value is only maintained correctly for the root of the corresponding object tree; other objects in the tree will have older values to facilitate backtracking.
| bool regina::GluingPermSearcher< 4 >::PentTriangleState::hadEqualRank |
Did this tree have rank equal to its parent immediately before it was grafted beneath its parent? This information is used to maintain the ranks correctly when grafting operations are undone.
If this object is still the root of its tree, this value is set to false.
| int regina::GluingPermSearcher< 4 >::PentTriangleState::parent |
The index of the parent object in the current tree, or -1 if this object is the root of the tree.
| unsigned regina::GluingPermSearcher< 4 >::PentTriangleState::rank |
The depth of the subtree beneath this object (where a leaf node has depth zero).
| unsigned regina::GluingPermSearcher< 4 >::PentTriangleState::size |
The total number of objects in the subtree descending from this object (where this object is counted also).
| Perm<3> regina::GluingPermSearcher< 4 >::PentTriangleState::twistUp |
The vertices of each pentachoron triangle can be labelled (0,1,2) by running through the underlying pentachoron vertices from smallest index to largest index.
The parameter twistUp is a permutation that maps vertices (0,1,2) of this triangle to vertices (0,1,2) of its parent in the tree according to the way in which the two triangles are identified. If this object has no parent, the value of twistUp is undefined.