Time Measuring and Counting

Detailed Description

This group contains simple tools for measuring the performance of algorithms.

Classes
class	Counter
	A counter class. More...
class	NoCounter
	'Do nothing' version of Counter. More...
class	TimeStamp
	A class to store (cpu)time instances. More...
class	Timer
	Class for measuring the cpu time and real time usage of the process. More...
class	TimeReport
	Same as Timer but prints a report on destruction. More...
class	NoTimeReport
	'Do nothing' version of TimeReport More...

Files
file	counter.h
	Tools for counting steps and events.
file	time_measure.h
	Tools for measuring cpu usage.

Functions
template<class F >
TimeStamp	runningTimeTest (F f, double min_time=10, unsigned int *num=NULL, TimeStamp *full_time=NULL)
	Tool to measure the running time more exactly.
std::ostream &	operator<< (std::ostream &os, const TimeStamp &t)
	Prints the time counters.

Function Documentation

TimeStamp lemon::runningTimeTest	(	F	f,
		double	min_time = 10,
		unsigned int *	num = NULL,
		TimeStamp *	full_time = NULL
	)

This function calls 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 min_time and 2*min_time.

Parameters

f	the function object to be measured.
min_time	the minimum total running time.

Return values

num	if it is not NULL, then the actual number of execution of f will be written into *num.
full_time	if it is not NULL, then the actual total running time will be written into *full_time.

Returns

The average running time of f.

std::ostream & operator<< ( std::ostream &  os, const TimeStamp &  t  )

related

Prints the time counters in the following form:

u: XX.XXs s: XX.XXs cu: XX.XXs cs: XX.XXs real: XX.XXs

where the values are the

• u: user cpu time,
• s: system cpu time,
• cu: user cpu time of children,
• cs: system cpu time of children,
• real: real time.

Note

On WIN32 platform the cummulative values are not calculated.