Re: [xsl] generating unique random numbers

[a kusa <akusa8@xxxxxxxxx>]

Thank you for all your responses.

What I did was to call math:random() twice and adding the results each
time around. And I used distinct-values() everytime.

Do you think this is a good approach?



On Mon, Feb 22, 2010 at 8:21 AM, Dimitre Novatchev <dnovatchev@xxxxxxxxx>
wrote:
> Hi Abel,
>
>> course. But Dimitre's XSLT-only approach to pseudo-random numbers in FXSL,
>> combined with distinct-values() will probably be a better course of
action.
>
> No need to add anything to the random - generating  functions of FXSL.
> There is already one:
>
> Templates: _
>
>      _randomRecursiveIndex
> and
>     _permutationFromRecursiveIndex
>
>
> Here is a fragment from the test file testRandomList.xsl, which can be
> fuuly viewed at:
>
>
http://fxsl.cvs.sourceforge.net/viewvc/fxsl/fxsl-xslt2/Tests/testRandomList.x
sl?revision=1.2&view=markup
>
>
>    Random Recursive Index 10:
>
>    <xsl:variable name="vrtfRecIndex">
>      <xsl:call-template name="_randomRecursiveIndex">
>        <xsl:with-param name="pList"
>        select="1  to 10"/>
>      </xsl:call-template>
>    </xsl:variable>
>
>    <xsl:variable name="vRecIndex"
>              select="$vrtfRecIndex/*"/>
>
>    <xsl:for-each select="$vRecIndex">
>      <xsl:copy-of select="."/>&#xA;
>    </xsl:for-each>
>
>    Randomized 10-elements list:
>    <xsl:call-template name="_permutationFromRecursiveIndex">
>      <xsl:with-param name="pList" select="1  to 10"/>
>      <xsl:with-param name="pRecIndex" select="$vRecIndex"/>
>    </xsl:call-template>
>
>
> And this produces the following part of the output:
>
>    Random Recursive Index 10:
>
>    <el>3</el>
> <el>9</el>
> <el>2</el>
> <el>6</el>
> <el>5</el>
> <el>1</el>
> <el>2</el>
> <el>3</el>
> <el>2</el>
> <el>1</el>
>
>    Randomized 10-elements list:
>    <el>3</el>
> <el>10</el>
> <el>2</el>
> <el>8</el>
> <el>7</el>
> <el>1</el>
> <el>5</el>
> <el>9</el>
> <el>6</el>
> <el>4</el>
>
>
>
>
> Anyone can use this *now* (or up to four years ago)  to get a
> randomized permutation of the set [1 .. N]
>
>
> --
> Cheers,
> Dimitre Novatchev
> ---------------------------------------
> Truly great madness cannot be achieved without significant intelligence.
> ---------------------------------------
> To invent, you need a good imagination and a pile of junk
> -------------------------------------
> Never fight an inanimate object
> -------------------------------------
> You've achieved success in your field when you don't know whether what
> you're doing is work or play
>
>
>
>
> On Mon, Feb 22, 2010 at 2:36 AM, Abel Braaksma <abel.online@xxxxxxxxx>
wrote:
>> As an alternative to the already proposed solutions, consider looking up
the
>> pseudo-random method to create GUIDs in XSLT, which I cooked up a few
years
>> ago: http://markmail.org/message/4zxb654yeaf5twnv
>>
>> It is random enough between runs (and sequential, yet non-repeating, in
one
>> run), but maybe not random enough for you. You can elaborate on the code,
of
>> course. But Dimitre's XSLT-only approach to pseudo-random numbers in FXSL,
>> combined with distinct-values() will probably be a better course of
action.
>>
>> Kind regards,
>> Abel Braaksma
>>
>> Wolfgang Laun wrote:
>>>
>>> What you describe is not a sequence of random numbers; a rule such as
>>> "no duplicates" contradicts most definitions of "randomness". What you
>>> request is better described as "a random permutation of numbers". This
>>> could
>>> be produced by random draws from a set of numbers (without returning)
>>> provided that you can, somehow, define this set. Can you?
>>>
>>> I regret that I'm not experienced enough to propose an XSLT solution
>>> for such an algorithm.
>>>
>>> -W
>>>
>>> On Sun, Feb 21, 2010 at 3:02 AM, a kusa <akusa8@xxxxxxxxx> wrote:
>>>
>>>>
>>>> Hi
>>>>
>>>> I have been raking my brains to achieve this. I am using math.random()
>>>> to generate random numbers, but of course since they repeat, I want to
>>>> be able to generate unique random numbers. Can anybody please help me
>>>> here? How can I generate unique random numbers in xslt?
>>>>
>>>> Thanks in advance for all your support.