diff -r e47fb28cda5e -r 82a2639a05bb lemon/time_measure.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lemon/time_measure.h	Sun Mar 30 22:16:35 2008 +0100
@@ -0,0 +1,541 @@
+/* -*- C++ -*-
+ *
+ * This file is a part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2003-2008
+ * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Research Group on Combinatorial Optimization, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_TIME_MEASURE_H
+#define LEMON_TIME_MEASURE_H
+
+///\ingroup timecount
+///\file
+///\brief Tools for measuring cpu usage
+
+#include <sys/times.h>
+
+#include <sys/time.h>
+#include <fstream>
+#include <iostream>
+#include <unistd.h>
+
+namespace lemon {
+
+  /// \addtogroup timecount
+  /// @{
+
+  /// A class to store (cpu)time instances.
+
+  /// This class stores five time values.
+  /// - a real time
+  /// - a user cpu time
+  /// - a system cpu time
+  /// - a user cpu time of children
+  /// - a system cpu time of children
+  ///
+  /// TimeStamp's can be added to or substracted from each other and
+  /// they can be pushed to a stream.
+  ///
+  /// In most cases, perhaps the \ref Timer or the \ref TimeReport
+  /// class is what you want to use instead.
+  ///
+  ///\author Alpar Juttner
+
+  class TimeStamp
+  {
+    struct rtms 
+    {
+      double tms_utime;
+      double tms_stime;
+      double tms_cutime;
+      double tms_cstime;
+      rtms() {}
+      rtms(tms ts) : tms_utime(ts.tms_utime), tms_stime(ts.tms_stime),
+		     tms_cutime(ts.tms_cutime), tms_cstime(ts.tms_cstime) {}
+    };
+    rtms ts;
+    double real_time;
+  
+    rtms &getTms() {return ts;}
+    const rtms &getTms() const {return ts;}
+
+    void _reset() { 
+      ts.tms_utime = ts.tms_stime = ts.tms_cutime = ts.tms_cstime = 0; 
+      real_time = 0;
+    }
+
+  public:
+
+    ///Read the current time values of the process
+    void stamp()
+    {
+      timeval tv;
+      tms _ts;
+      times(&_ts);
+      gettimeofday(&tv, 0);real_time=tv.tv_sec+double(tv.tv_usec)/1e6;
+      ts=_ts;
+    }
+  
+    /// Constructor initializing with zero
+    TimeStamp()
+    { _reset(); }
+    ///Constructor initializing with the current time values of the process
+    TimeStamp(void *) { stamp();}
+  
+    ///Set every time value to zero
+    TimeStamp &reset() {_reset();return *this;}
+
+    ///\e
+    TimeStamp &operator+=(const TimeStamp &b)
+    {
+      ts.tms_utime+=b.ts.tms_utime;
+      ts.tms_stime+=b.ts.tms_stime;
+      ts.tms_cutime+=b.ts.tms_cutime;
+      ts.tms_cstime+=b.ts.tms_cstime;
+      real_time+=b.real_time;
+      return *this;
+    }
+    ///\e
+    TimeStamp operator+(const TimeStamp &b) const
+    {
+      TimeStamp t(*this);
+      return t+=b;
+    }
+    ///\e
+    TimeStamp &operator-=(const TimeStamp &b)
+    {
+      ts.tms_utime-=b.ts.tms_utime;
+      ts.tms_stime-=b.ts.tms_stime;
+      ts.tms_cutime-=b.ts.tms_cutime;
+      ts.tms_cstime-=b.ts.tms_cstime;
+      real_time-=b.real_time;
+      return *this;
+    }
+    ///\e
+    TimeStamp operator-(const TimeStamp &b) const
+    {
+      TimeStamp t(*this);
+      return t-=b;
+    }
+    ///\e
+    TimeStamp &operator*=(double b)
+    {
+      ts.tms_utime*=b;
+      ts.tms_stime*=b;
+      ts.tms_cutime*=b;
+      ts.tms_cstime*=b;
+      real_time*=b;
+      return *this;
+    }
+    ///\e
+    TimeStamp operator*(double b) const
+    {
+      TimeStamp t(*this);
+      return t*=b;
+    }
+    friend TimeStamp operator*(double b,const TimeStamp &t);
+    ///\e
+    TimeStamp &operator/=(double b)
+    {
+      ts.tms_utime/=b;
+      ts.tms_stime/=b;
+      ts.tms_cutime/=b;
+      ts.tms_cstime/=b;
+      real_time/=b;
+      return *this;
+    }
+    ///\e
+    TimeStamp operator/(double b) const
+    {
+      TimeStamp t(*this);
+      return t/=b;
+    }
+    ///The time ellapsed since the last call of stamp()
+    TimeStamp ellapsed() const
+    {
+      TimeStamp t(NULL);
+      return t-*this;
+    }
+  
+    friend std::ostream& operator<<(std::ostream& os,const TimeStamp &t);
+  
+    ///Gives back the user time of the process
+    double userTime() const
+    {
+      return double(ts.tms_utime)/sysconf(_SC_CLK_TCK);
+    }
+    ///Gives back the system time of the process
+    double systemTime() const
+    {
+      return double(ts.tms_stime)/sysconf(_SC_CLK_TCK);
+    }
+    ///Gives back the user time of the process' children
+    double cUserTime() const
+    {
+      return double(ts.tms_cutime)/sysconf(_SC_CLK_TCK);
+    }
+    ///Gives back the user time of the process' children
+    double cSystemTime() const
+    {
+      return double(ts.tms_cstime)/sysconf(_SC_CLK_TCK);
+    }
+    ///Gives back the real time
+    double realTime() const {return real_time;}
+  };
+
+  TimeStamp operator*(double b,const TimeStamp &t) 
+  {
+    return t*b;
+  }
+  
+  ///Prints the time counters
+
+  ///Prints the time counters in the following form:
+  ///
+  /// <tt>u: XX.XXs s: XX.XXs cu: XX.XXs cs: XX.XXs real: XX.XXs</tt>
+  ///
+  /// where the values are the
+  /// \li \c u: user cpu time,
+  /// \li \c s: system cpu time,
+  /// \li \c cu: user cpu time of children,
+  /// \li \c cs: system cpu time of children,
+  /// \li \c real: real time.
+  /// \relates TimeStamp
+  inline std::ostream& operator<<(std::ostream& os,const TimeStamp &t)
+  {
+    long cls = sysconf(_SC_CLK_TCK);
+    os << "u: " << double(t.getTms().tms_utime)/cls <<
+      "s, s: " << double(t.getTms().tms_stime)/cls <<
+      "s, cu: " << double(t.getTms().tms_cutime)/cls <<
+      "s, cs: " << double(t.getTms().tms_cstime)/cls <<
+      "s, real: " << t.realTime() << "s";
+    return os;
+  }
+
+  ///Class for measuring the cpu time and real time usage of the process
+
+  ///Class for measuring the cpu time and real time usage of the process.
+  ///It is quite easy-to-use, here is a short example.
+  ///\code
+  /// #include<lemon/time_measure.h>
+  /// #include<iostream>
+  ///
+  /// int main()
+  /// {
+  ///
+  ///   ...
+  ///
+  ///   Timer t;
+  ///   doSomething();
+  ///   std::cout << t << '\n';
+  ///   t.restart();
+  ///   doSomethingElse();
+  ///   std::cout << t << '\n';
+  ///
+  ///   ...
+  ///
+  /// }
+  ///\endcode
+  ///
+  ///The \ref Timer can also be \ref stop() "stopped" and
+  ///\ref start() "started" again, so it is possible to compute collected
+  ///running times.
+  ///
+  ///\warning Depending on the operation system and its actual configuration
+  ///the time counters have a certain (10ms on a typical Linux system)
+  ///granularity.
+  ///Therefore this tool is not appropriate to measure very short times.
+  ///Also, if you start and stop the timer very frequently, it could lead to
+  ///distorted results.
+  ///
+  ///\note If you want to measure the running time of the execution of a certain
+  ///function, consider the usage of \ref TimeReport instead.
+  ///
+  ///\todo This shouldn't be Unix (Linux) specific.
+  ///\sa TimeReport
+  ///
+  ///\author Alpar Juttner
+  class Timer
+  {
+    int _running; //Timer is running iff _running>0; (_running>=0 always holds)
+    TimeStamp start_time; //This is the relativ start-time if the timer
+                          //is _running, the collected _running time otherwise.
+    
+    void _reset() {if(_running) start_time.stamp(); else start_time.reset();}
+  
+  public: 
+    ///Constructor.
+
+    ///\param run indicates whether or not the timer starts immediately.
+    ///
+    Timer(bool run=true) :_running(run) {_reset();}
+
+    ///\name Control the state of the timer
+    ///Basically a Timer can be either running or stopped,
+    ///but it provides a bit finer control on the execution.
+    ///The \ref Timer also counts the number of \ref start()
+    ///executions, and is stops only after the same amount (or more)
+    ///\ref stop() "stop()"s. This can be useful e.g. to compute the running time
+    ///of recursive functions.
+    ///
+
+    ///@{
+
+    ///Reset and stop the time counters
+
+    ///This function resets and stops the time counters
+    ///\sa restart()
+    void reset()
+    {
+      _running=0;
+      _reset();
+    }
+
+    ///Start the time counters
+    
+    ///This function starts the time counters.
+    ///
+    ///If the timer is started more than ones, it will remain running
+    ///until the same amount of \ref stop() is called.
+    ///\sa stop()
+    void start() 
+    {
+      if(_running) _running++;
+      else {
+	_running=1;
+	TimeStamp t;
+	t.stamp();
+	start_time=t-start_time;
+      }
+    }
+
+    
+    ///Stop the time counters
+
+    ///This function stops the time counters. If start() was executed more than
+    ///once, then the same number of stop() execution is necessary the really
+    ///stop the timer.
+    /// 
+    ///\sa halt()
+    ///\sa start()
+    ///\sa restart()
+    ///\sa reset()
+
+    void stop() 
+    {
+      if(_running && !--_running) {
+	TimeStamp t;
+	t.stamp();
+	start_time=t-start_time;
+      }
+    }
+
+    ///Halt (i.e stop immediately) the time counters
+
+    ///This function stops immediately the time counters, i.e. <tt>t.stop()</tt>
+    ///is a faster
+    ///equivalent of the following.
+    ///\code
+    ///  while(t.running()) t.stop()
+    ///\endcode
+    ///
+    ///
+    ///\sa stop()
+    ///\sa restart()
+    ///\sa reset()
+
+    void halt() 
+    {
+      if(_running) {
+	_running=0;
+	TimeStamp t;
+	t.stamp();
+	start_time=t-start_time;
+      }
+    }
+
+    ///Returns the running state of the timer
+
+    ///This function returns the number of stop() exections that is
+    ///necessary to really stop the timer.
+    ///For example the timer
+    ///is running if and only if the return value is \c true
+    ///(i.e. greater than
+    ///zero).
+    int running()  { return _running; }
+    
+    
+    ///Restart the time counters
+
+    ///This function is a shorthand for
+    ///a reset() and a start() calls.
+    ///
+    void restart() 
+    {
+      reset();
+      start();
+    }
+    
+    ///@}
+
+    ///\name Query Functions for the ellapsed time
+
+    ///@{
+
+    ///Gives back the ellapsed user time of the process
+    double userTime() const
+    {
+      return operator TimeStamp().userTime();
+    }
+    ///Gives back the ellapsed system time of the process
+    double systemTime() const
+    {
+      return operator TimeStamp().systemTime();
+    }
+    ///Gives back the ellapsed user time of the process' children
+    double cUserTime() const
+    {
+      return operator TimeStamp().cUserTime();
+    }
+    ///Gives back the ellapsed user time of the process' children
+    double cSystemTime() const
+    {
+      return operator TimeStamp().cSystemTime();
+    }
+    ///Gives back the ellapsed real time
+    double realTime() const
+    {
+      return operator TimeStamp().realTime();
+    }
+    ///Computes the ellapsed time
+
+    ///This conversion computes the ellapsed time, therefore you can print
+    ///the ellapsed time like this.
+    ///\code
+    ///  Timer t;
+    ///  doSomething();
+    ///  std::cout << t << '\n';
+    ///\endcode
+    operator TimeStamp () const
+    {
+      TimeStamp t;
+      t.stamp();
+      return _running?t-start_time:start_time;
+    }
+
+
+    ///@}
+  };
+
+  ///Same as \ref Timer but prints a report on destruction.
+
+  ///Same as \ref Timer but prints a report on destruction.
+  ///This example shows its usage.
+  ///\code
+  ///  void myAlg(ListGraph &g,int n)
+  ///  {
+  ///    TimeReport tr("Running time of myAlg: ");
+  ///    ... //Here comes the algorithm
+  ///  }
+  ///\endcode
+  ///
+  ///\sa Timer
+  ///\sa NoTimeReport
+  ///\todo There is no test case for this
+  class TimeReport : public Timer 
+  {
+    std::string _title;
+    std::ostream &_os;
+  public:
+    ///\e
+
+    ///\param title This text will be printed before the ellapsed time.
+    ///\param os The stream to print the report to.
+    ///\param run Sets whether the timer should start immediately.
+
+    TimeReport(std::string title,std::ostream &os=std::cerr,bool run=true) 
+      : Timer(run), _title(title), _os(os){}
+    ///\e Prints the ellapsed time on destruction.
+    ~TimeReport() 
+    {
+      _os << _title << *this << std::endl;
+    }
+  };
+      
+  ///'Do nothing' version of \ref TimeReport
+
+  ///\sa TimeReport
+  ///
+  class NoTimeReport
+  {
+  public:
+    ///\e
+    NoTimeReport(std::string,std::ostream &,bool) {}
+    ///\e
+    NoTimeReport(std::string,std::ostream &) {}
+    ///\e
+    NoTimeReport(std::string) {}
+    ///\e Do nothing.
+    ~NoTimeReport() {}
+
+    operator TimeStamp () const { return TimeStamp(); }
+    void reset() {}
+    void start() {}
+    void stop() {}
+    void halt() {} 
+    int running() { return 0; }
+    void restart() {}
+    double userTime() const { return 0; }
+    double systemTime() const { return 0; }
+    double cUserTime() const { return 0; }
+    double cSystemTime() const { return 0; }
+    double realTime() const { return 0; }
+  };
+      
+  ///Tool to measure the running time more exactly.
+  
+  ///This function calls \c f several times and returns the average
+  ///running time. The number of the executions will be choosen in such a way
+  ///that the full real running time will be roughly between \c min_time
+  ///and <tt>2*min_time</tt>.
+  ///\param f the function object to be measured.
+  ///\param min_time the minimum total running time.
+  ///\retval num if it is not \c NULL, then the actual
+  ///        number of execution of \c f will be written into <tt>*num</tt>.
+  ///\retval full_time if it is not \c NULL, then the actual
+  ///        total running time will be written into <tt>*full_time</tt>.
+  ///\return The average running time of \c f.
+  
+  template<class F>
+  TimeStamp runningTimeTest(F f,double min_time=10,unsigned int *num = NULL,
+                            TimeStamp *full_time=NULL)
+  {
+    TimeStamp full;
+    unsigned int total=0;
+    Timer t;
+    for(unsigned int tn=1;tn <= 1U<<31 && full.realTime()<=min_time; tn*=2) {
+      for(;total<tn;total++) f();
+      full=t;
+    }
+    if(num) *num=total;
+    if(full_time) *full_time=full;
+    return full/total;
+  }
+  
+  /// @}  
+
+
+} //namespace lemon
+
+#endif //LEMON_TIME_MEASURE_H