Re: Re: Re: exponential math functions in xslt

On Fri, 20 Sep 2002 05:03:08 -0700 (PDT), Dimitri wrote:

>
>--- Trevor Nash <tcn at melvaig dot co dot uk> wrote:
>
> 
>> On Thu, 19 Sep 2002 12:27:53 -0700 (PDT), Dimitri wrote:
>> 
>> >As for another myth -- that extension functions are significantly
>> >faster, I recently performed detailed timing in an XSLT application,
>> in
>> >which ln() was computed approx. 5000 times. Substitution of the FXSL
>> >"ln" template with calls to a Javascript extension function led to
>> less
>> >than 10% increase of the speed.
>> 
>> Why did you pick Javascript?
>> 
>> The numbers for a Java (not Javascript) extension called from a Java
>> based XSLT processor are likely to be different.
>
>Allow me to disagree with this. The Javascript extension does nothing
>else but call the standard math.log()
>
>And the math object itself will hardly be implemented in Javascript.
>Therefore, there's no reason why Javascript's math.log() would perform
>slower than its any other language counterpart.
>
True, except that you are invoking an interpreter in order to
determine that it is math.log() that you need to call - I'm just
guessing that the cost of doing that is significant (scanning,
parsing, symbol lookup...).  Are you saying the XSLT/Javascript
combination contrives to do this work just once per run?

Trevor
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