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/********************************************************************* |
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* * |
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* Copyright (c) 1997,1998, 1999 * |
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* Multimedia DB Group and DEIS - CSITE-CNR, * |
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* University of Bologna, Bologna, ITALY. * |
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* * |
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* All Rights Reserved. * |
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* * |
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* Permission to use, copy, and distribute this software and its * |
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* documentation for NON-COMMERCIAL purposes and without fee is * |
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* hereby granted provided that this copyright notice appears in * |
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* all copies. * |
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* * |
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* THE AUTHORS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE * |
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* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING * |
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* BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, * |
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* FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR * |
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* SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A * |
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* RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * |
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* DERIVATIVES. * |
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* * |
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*********************************************************************/ |
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|
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#ifndef MTCURSOR_H |
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#define MTCURSOR_H |
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|
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#ifndef MAXDOUBLE |
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#ifdef _WIN32 // for MAXDOUBLE |
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#include <float.h> |
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#define MAXDOUBLE DBL_MAX |
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#else |
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#include <values.h> |
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#endif |
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#endif |
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#include "GiST.h" |
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#include "list.h" |
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|
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class MT; |
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class MTentry; |
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class MTpred; |
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|
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class dst { // this class is used in the NN-search algorithm for the priority queue |
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public: |
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dst(): bound(0), d(MAXDOUBLE) {} |
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dst(GiSTpath p, double LB, double dist): bound(LB), d(dist), path(p) {} |
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|
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double Bound() const { return bound; } |
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double Dist() const { return d; } |
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GiSTpath Path() { return path; } |
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private: |
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double bound; |
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double d; |
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GiSTpath path; |
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}; |
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|
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int comparedst(dst *a, dst *b); |
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int comparedst(dst& a, dst& b); |
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|
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class MTcursor { |
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public: |
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MTcursor(const MT& tree, const MTpred& query); |
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MTentry *Next(); |
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BOOL IsReady() const; |
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double Bound() const; |
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~MTcursor(); |
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|
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private: |
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void FetchNode(); |
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|
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const MT& tree; |
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list<MTentry *> results; |
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list<dst *> queue; |
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MTpred *query; |
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}; |
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|
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#endif |