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Topic: Random numbers
Replies: 64   Last Post: Dec 24, 2007 1:04 PM

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quasi

Posts: 12,054
Registered: 7/15/05
Re: Random numbers
Posted: Dec 21, 2007 8:10 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On Fri, 21 Dec 2007 04:44:14 -0800, William Elliot
<marsh@hevanet.remove.com> wrote:

>On Fri, 21 Dec 2007, John wrote:
>

>> Given a function that returns a random number between 1-5, write one
>> that returns a random number between 1-7 for the case when it should
>> be integer and for the case it can be real.
>>

>Between 1 and 5 for real numbers means in (1,5).
>Given a random r in (1,5), 6(r - 1)/4 + 1 is random in (1,7).
>
>A random integer between 1 and 5 is 2, 3 or 4.
>A random integer between 1 and 7 is 2, 3, 4, 5 or 6.


In this context, "between" was probably intended to mean 1 to 7
_inclusive_.


>Let r be a random number in { 2,3,4 }.
>Let s = 0, if r = 2
> 1, if r = 3
>goto let s if r = 4
>
>s is a random binary number.
>
>Let t = 1 if r = 2, s = 0
> 2 if r = 2, s = 1
> 3 if r = 3, s = 0
> 4 if r = 4, s = 1
> 5 if r = 5, s = 0
> 6 if r = 6, s = 1


Very strange. How can r be 4,5,6? The variable r was generated as a
random integer from the set {2,3,4} with rejection and retry if r = 4,
so its value must be either 2 or 3.
>
>t is a random number in { 1,2,3,4,5.6 }.


??? How did you generate t? There's no mention of t before the above
line.
>
>Let d = t if t /= 1
>goto let d if t = 1


The above 2 lines yield an infinite loop if t = 1.

>d is a random number in { 2,3,4,5,6 }.

Even if your algorithm can be corrected so as to make sense, you're
making it more complicated than it needs to be.

quasi


Date Subject Author
12/21/07
Read Random numbers
Champ
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Marshall
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Phil Carmody
12/21/07
Read Re: Random numbers
Marshall
12/21/07
Read Re: Random numbers
briggs@encompasserve.org
12/21/07
Read Re: Random numbers
William Elliot
12/21/07
Read Re: Random numbers
quasi
12/22/07
Read Re: Random numbers
William Elliot
12/21/07
Read Re: Random numbers
Pubkeybreaker
12/21/07
Read Re: Random numbers
b92057@yahoo.com
12/22/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
simple.popeye@gmail.com
12/21/07
Read Re: Random numbers
simple.popeye@gmail.com
12/22/07
Read Re: Random numbers
quasi
12/22/07
Read Re: Random numbers
Gib Bogle
12/22/07
Read Re: Random numbers
quasi
12/21/07
Read Re: Random numbers
Marshall
12/22/07
Read Re: Random numbers
simple.popeye@gmail.com
12/22/07
Read Re: Random numbers
quasi
12/22/07
Read Re: Random numbers
simple.popeye@gmail.com
12/22/07
Read Re: Random numbers
quasi
12/22/07
Read Re: Random numbers
quasi
12/22/07
Read Re: Random numbers
quasi
12/22/07
Read Re: Random numbers
simple.popeye@gmail.com
12/22/07
Read Re: Random numbers
quasi
12/23/07
Read Re: Random numbers
simple.popeye@gmail.com
12/23/07
Read Re: Random numbers
simple.popeye@gmail.com
12/23/07
Read Re: Random numbers
simple.popeye@gmail.com
12/23/07
Read Re: Random numbers
simple.popeye@gmail.com
12/23/07
Read Re: Random numbers
simple.popeye@gmail.com
12/22/07
Read Re: Random numbers
adder
12/22/07
Read Re: Random numbers
simple.popeye@gmail.com
12/22/07
Read Re: Random numbers
Herman Rubin
12/22/07
Read Re: Random numbers
adder
12/22/07
Read Re: Random numbers
b92057@yahoo.com
12/22/07
Read Re: Random numbers
quasi
12/23/07
Read Re: Random numbers
b92057@yahoo.com
12/23/07
Read Re: Random numbers
quasi
12/23/07
Read Re: Random numbers
b92057@yahoo.com
12/24/07
Read Re: Random numbers
quasi
12/24/07
Read Re: Random numbers
quasi
12/24/07
Read Re: Random numbers
adder
12/24/07
Read Re: Random numbers
quasi
12/24/07
Read Re: Random numbers
adder
12/24/07
Read Re: Random numbers
b92057@yahoo.com

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