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Re: Seeding random() randomly
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Re: Seeding random() randomly


  • Subject: Re: Seeding random() randomly
  • From: Eeyore <email@hidden>
  • Date: Thu, 26 May 2011 20:18:35 -0700

I've seen gnu documentation for srandom that suggest the equivalent of Kevin's suggestion, namely "srandom(time(0))". Not sure if using the NSDate has any advantage over a call to time() and it would avoid this type of thing (gnu is likely to ensure time() and srandom() work correctly together).

Aaron

On May 26, 2011, at 8:10 PM, Chase Latta wrote:

> unsigned seed = (unsigned)([NSDate timeIntervalSinceReferenceDate] * 10000.0);
>
> You are trying to set seed to a value that is something like
> 3,281,585,690,000; seed cannot handle this value so it will be set to
> 4294967295, at least on my machine.
>
> You are using the same seed each time you run the program so you are
> getting the same values.  Try getting rid of the "* 10000.0".
>
> Chase
>
> On Thu, May 26, 2011 at 7:15 PM, Kevin Bracey <email@hidden> wrote:
>> I think this was from some programming book I have, sorry I can site it:
>>
>> srandom(time(NULL));
>>
>> cheers
>> Kevin
>>
>>
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References: 
 >Re: Seeding random() randomly (From: Kevin Bracey <email@hidden>)
 >Re: Seeding random() randomly (From: Chase Latta <email@hidden>)

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