GEOS  3.8.0dev
DoubleBits.h
1 /**********************************************************************
2  *
3  * GEOS - Geometry Engine Open Source
4  * http://geos.osgeo.org
5  *
6  * Copyright (C) 2006 Refractions Research Inc.
7  *
8  * This is free software; you can redistribute and/or modify it under
9  * the terms of the GNU Lesser General Public Licence as published
10  * by the Free Software Foundation.
11  * See the COPYING file for more information.
12  *
13  **********************************************************************
14  *
15  * Last port: index/quadtree/DoubleBits.java rev. 1.7 (JTS-1.10)
16  *
17  **********************************************************************/
18 
19 #ifndef GEOS_IDX_QUADTREE_DOUBLEBITS_H
20 #define GEOS_IDX_QUADTREE_DOUBLEBITS_H
21 
22 #include <geos/export.h>
23 #include <geos/constants.h> // for int64
24 
25 #include <string>
26 
27 namespace geos {
28 namespace index { // geos::index
29 namespace quadtree { // geos::index::quadtree
30 
31 
44 class GEOS_DLL DoubleBits {
45 
46 public:
47 
48  static const int EXPONENT_BIAS = 1023;
49 
50  static double powerOf2(int exp);
51 
52  static int exponent(double d);
53 
54  static double truncateToPowerOfTwo(double d);
55 
56  static std::string toBinaryString(double d);
57 
58  static double maximumCommonMantissa(double d1, double d2);
59 
60  DoubleBits(double nx);
61 
62  double getDouble() const;
63 
65  int64 biasedExponent() const;
66 
68  int getExponent() const;
69 
70  void zeroLowerBits(int nBits);
71 
72  int getBit(int i) const;
73 
86  int numCommonMantissaBits(const DoubleBits& db) const;
87 
89  std::string toString() const;
90 
91 private:
92 
93  double x;
94 
95  int64 xBits;
96 };
97 
98 } // namespace geos::index::quadtree
99 } // namespace geos::index
100 } // namespace geos
101 
102 #endif // GEOS_IDX_QUADTREE_DOUBLEBITS_H
Basic namespace for all GEOS functionalities.
Definition: IndexedNestedRingTester.h:25
DoubleBits manipulates Double numbers by using bit manipulation and bit-field extraction.
Definition: DoubleBits.h:44