edu.princeton.cs.algs4

Class Stopwatch

java.lang.Object

edu.princeton.cs.algs4.Stopwatch

public class Stopwatch
extends java.lang.Object

The Stopwatch data type is for measuring the time that elapses between the start and end of a programming task (wall-clock time). See StopwatchCPU for a version that measures CPU time. For additional documentation, see Section 1.4 of Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.

Constructor Summary

Constructors

Constructor and Description
Stopwatch() Initializes a new stopwatch.

Method Summary

Modifier and Type	Method and Description
double	elapsedTime() Returns the elapsed CPU time (in seconds) since the stopwatch was created.
static void	main(java.lang.String[] args) Unit tests the Stopwatch data type.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Stopwatch

public Stopwatch()

Initializes a new stopwatch.

Method Detail

elapsedTime

public double elapsedTime()

Returns the elapsed CPU time (in seconds) since the stopwatch was created.

Returns:

elapsed CPU time (in seconds) since the stopwatch was created

main

public static void main(java.lang.String[] args)

Unit tests the Stopwatch data type. Takes a command-line argument n and computes the sum of the square roots of the first n positive integers, first using Math.sqrt(), then using Math.pow(). It prints to standard output the sum and the amount of time to compute the sum. Note that the discrete sum can be approximated by an integral - the sum should be approximately 2/3 * (n^(3/2) - 1).

Parameters:

args - the command-line arguments