class KRandomSequence

A class to create a pseudo-random sequence More...

Definition#include <krandomsequence.h>
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Detailed Description

A class to create a pseudo-random sequence

Given a seed number, this class will produce a sequence of pseudo-random numbers. This would typically be used in applications like games.

In general, you should instantiate a KRandomSequence object and pass along your seed number in the constructor. From then on, simply call getDouble or getLong to obtain the next number in the sequence.

 KRandomSequence ( long lngSeed = 0 )

KRandomSequence

Creates a pseudo-random sequence based on the seed lngSeed.

If lngSeed is 0, the sequence is initialized with a value from kapp->random().

A Pseudo-random sequence is different for each seed but can be reproduced by starting the sequence with the same seed.

If you need a single value which needs to be unpredictable, you need to use kapp->random() instead.

Parameters:
lngSeedSeed to initialize the sequence with.

 ~KRandomSequence ()

~KRandomSequence

[virtual]

Standard destructor

 KRandomSequence (const KRandomSequence &a)

KRandomSequence

Copy constructor

KRandomSequenceoperator= (const KRandomSequence &a)

operator=

Assignment

void  setSeed ( long lngSeed = 1 )

setSeed

Restart the sequence based on lngSeed

double  getDouble ()

getDouble

Get the next number from the pseudo-random sequence

Returns: a psuedo-random double value between [0,1[

unsigned long  getLong (unsigned long max)

getLong

Get the next number from the pseudo-random sequence

Returns: a pseudo-random integer value between [0, max[ with 0 <= max < 1.000.000

bool  getBool ()

getBool

Get a boolean from the pseudo-random sequence

Returns: a boolean which is either true or false

void  randomize (QGList *list)

randomize

Put a list in random order

Returns: modifies the order of list

void  modulate (int i)

modulate

Modulate the random sequence.

If S(i) is the sequence of numbers that will follow given the current state after calling modulate(i), then S(i) != S(j) for i != j and S(i) == S(j) for i == j.

This can be usefull in game situation where "undo" restores the state of the random sequence. If the game modulates the random sequence with the move chosen by the player, the random sequence will be identical whenever the player "redo"-s his or hers original move, but different when the player chooses another move.

With this scenario "undo" can no longer be used to repeat a certain move over and over again until the computer reacts with a favourable response or to predict the response for a certain move based on the response to another move.