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Thread: Period

  1. #1
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    Default Period

    One of the random number generators in Java extract the higher-order bits of the random number in order to get a longer period.

    I'm not sure if I understand how this is done. Suppose that the random number r = 0000 1100 1000 1101. If we extract the 16 most significant bits from r; is the new number r = 0000 1100 or r = 0000 1100 0000 0000?


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    Default Re: Period

    One of the random number generators in Java
    Can you specify which random number generator you're talking about and provide a reference for the functional description you've given?

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    Default Re: Period

    From Linear congruential generator - Wikipedia, the free encyclopedia
    As shown above, LCGs do not always use all of the bits in the values they produce. For example, the Java implementation operates with 48-bit values at each iteration but returns only their 32 most significant bits. This is because the higher-order bits have longer periods than the lower-order bits (see below). LCGs that use this truncation technique produce statistically better values than those that do not.

    java.util.Random

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    Default Re: Period

    You might find the Random source code helpful. Maybe not.

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