Re: Random number seed generation

Out of curiosity: Usually, a random generator's seed needs only one setting
so that you get different sequences with different program runs. Resetting
the RG with a different seed every now and then isn't bound to make the
sequence any "randomer".

So why?
-W

On 9 December 2010 15:04, Michel Hendriksen <michel.hendriksen@xxxxx> wrote:
>
> Hi all,
>
> I'm using Saxon9he processor XSLT 2.0, and I am trying to get some
> random numbers. I'm currently using fxsl/random for this. The problem
> is that it needs a seed.
> I tried using current time stuff but that doesn't change during the
> transfomation using the stylesheet.. So I tried an extension function
> to cal to Java but that doesn't seem to work. Examples are probably
> XSLT 1.0 but should be ok.
>
> Is this possible on Home Edition? Did things change in transition to
> 2.0? Is there an other way to get some seed for the random function? I
> can't resuse the value as I would have to keep it somewhere in between
> calls. One idea would be to use generate-id() but that gives a string.
> Could be useful when this is always convertible to a number.
>
> I'm running the processor from a Java application now. It is a
> learning project and should be able to run Genetic Algorithm
> functionality, so lots of random stuff is needed.
>
> Tried:
>
>   <xslt:value-of select="math:sqrt(10)" xmlns:math="java:java.lang.Math"/>
>
>   <xslt:variable name="date" select="date:new()"
> xmlns:date="java:java.util.Date"/>
>
> As samples for getting something but errors are:
>
> Error at xslt:value-of on line 62 column 74 of selector.xsl:
>  XPST0017: XPath syntax error at char 13 on line 62 in {math:sqrt(10)}:
>   Cannot find a matching 1-argument function named
{java:java.lang.Math}sqrt()
> Error at xslt:variable on line 64 column 83 of selector.xsl:
>  XPST0017: XPath syntax error at char 10 on line 64 in {date:new()}:
>   Cannot find a matching 0-argument function named
{java:java.util.Date}new()
>
>
> Michel Hendriksen