Chronograph

class Chronograph

Simple timer class that allows to measure elapsed times in real seconds as well as CPU used sec

Public Methods
Chronograph(): creator - no arguments - starts also the Chronograph
~Chronograph(): destructor - does nothing

Public

getting the time information of the chronograph

double lap(): returns the number of CPU seconds since the last time lap was called
double elapsed(): returns the number of CPU seconds
double time_interval(): returns the total time interval (i.e. not the CPU seconds)
double elapsedHMS(double &Hours, double &Mins, double &Secs): returns the elapsed time in seconds as well as Hours, Mins and Secs

starting and stopping the chronograph

double start(): reset and start the chronograph
double stop(): stop it and return the time since start
int isstopped(): returns non-zero if stopped (i.e. the value of the private member)
double reset(): stops the chronograph and initializes all the time to the current time

Private Fields
double _elapsed: the last elapsed time taken
clock_t _lastlap: when the last lap was read
clock_t _start: when the Chronograph was started
struct timespec _start_time: in keep track how many (real time) sec have passed
clock_t _stopped: when the Chronograph was stopped, if _stopped != 0 it is stopped

Private Methods
double diff(clock_t start, clock_t end): diff() calculates the difference IN SECONDS between two clock_t values.

Documentation

Simple timer class that allows to measure elapsed times in real seconds as well as CPU used sec. (pirated from CUJ)
Note that the Chronograph keeps track of the CPU seconds as well as the real seconds passed. Thus one can use it for measureing the actual time a piece of code takes as well as the number of seconds that it takes in total.
USAGE:
     Chronograph *my_chrono = new Chronograph();
     // do something
     my_chrono->stop();
     double nSecCpu = my_chrono->elapsed();
     double nSecTotal = my_chrono->time_interval();

     my_chrono->start(); // note start also resets the Chronograph
     
     // etc etc
MODIFICATIONS :

Dec 14, 1997: add #ifdef IRIX as IRIX 5.3 does not support CLOCK_REALTIME
Mar 21, 1998: check that it works on Linux