dither.h
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34 
37 #ifndef CONTROL_TOOLBOX__DITHER_H
38 #define CONTROL_TOOLBOX__DITHER_H
39 
40 #include <cstdlib>
41 #include <ctime>
42 #include <math.h>
43 #include <ros/ros.h>
44 
45 namespace control_toolbox {
46 
47 /***************************************************/
57 class Dither
58 {
59 public:
60 
61  Dither();
62 
66  ~Dither();
67 
72  double update();
73 
74  /*
75  *\brief Dither gets an amplitude, must be >0 to initialize
76  *
77  *\param amplitude Amplitude of white noise output
78  *\param seed Random seed for white noise
79  */
80  bool init(const double &amplitude, const double &seed)
81  {
82  if (amplitude < 0.0)
83  {
84  ROS_ERROR("Dither amplitude not set properly. Amplitude must be >0.");
85  return false;
86  }
87 
88  amplitude_ = amplitude;
89 
90  // Somewhat mimics the old code. A given seed gives a
91  // reproducible sequence of random numbers, and that's what
92  // matters.
93  unsigned long s = (unsigned long)seed;
94  seed_[0] = (s) ^ 45213;
95  seed_[1] = (s >> 16) ^ 39204;
96  seed_[2] = (s >> 32) ^ 5598;
97 
98  return true;
99  }
100 
101 
102 private:
103  double amplitude_;
104  double saved_value_;
106  double s_;
107  double x_;
108  unsigned short seed_[3];
109 };
110 }
111 
112 #endif
~Dither()
Destructor.
Definition: dither.cpp:46
XmlRpcServer s
Gives white noise at specified amplitude.
Definition: dither.h:57
bool init(const double &amplitude, const double &seed)
Definition: dither.h:80
double update()
Get next Gaussian white noise point. Called in RT loop.
Definition: dither.cpp:50
unsigned short seed_[3]
Definition: dither.h:108
#define ROS_ERROR(...)


control_toolbox
Author(s): Melonee Wise, Sachin Chitta, John Hsu
autogenerated on Mon Jun 10 2019 12:56:31