R help - Feb 2009 - Calculating variables

Dear fellows: This is the problem: I have 5 variables A, B, C, D and E  
with a range from 1 to 100 with 0.1 steps. Depending on the different  
values these have, the results of the formula change:

alitemp  <- ((Abase/llmcc$Clase)*PClase)+(((1/llmcc 
$Categoria)*Abase)*PCategoria)+((Abase*llmcc$Phi)*PPhi)+((Abase*llmcc 
$Rf)*PRf)

So, alitemp (a 283 element series) changes if any of the P** values  
changes. I need to find a combinations of those 5 variables that  
approximates the desired results. Although I can make use of a 'for'  
loop, Im not sure of how to combine the whole 5 variables changing at  
once. I understand there are many possible combinations (factorial of  
5000!, 422 with some 500 digits) but I surmise there must be a better  
way to do it.
So far, I have been changing them manually, but this task make the  
whole thing terribly slow and inneficient.
Any ideas are appreciated.
Thanks.

Cuanto mas grande son, mas daño hacen. Postulado de Perkin.
------------------------------
Jesús Guillermo Andrade (Abg.)
Gerente de Litigios y Corporativo. EDM. AC. API.
Andrade & Moreno S.C. (http://amlegal.wordpress.com/)


	[[alternative HTML version deleted]]

Jes?s Guillermo Andrade wrote:
> Dear fellows: This is the problem: I have 5 variables A, B, C, D and E  
> with a range from 1 to 100 with 0.1 steps. Depending on the different  
> values these have, the results of the formula change:
> 
> alitemp  <- ((Abase/llmcc$Clase)*PClase)+(((1/llmcc 
> $Categoria)*Abase)*PCategoria)+((Abase*llmcc$Phi)*PPhi)+((Abase*llmcc 
> $Rf)*PRf)
>

There is no instance of A...E in that formula, is it?

> So, alitemp (a 283 element series) changes if any of the P** values  
> changes. I need to find a combinations of those 5 variables that  
> approximates the desired results. Although I can make use of a
'for'
> loop, Im not sure of how to combine the whole 5 variables changing at  
> once. I understand there are many possible combinations (factorial of  
> 5000!, 422 with some 500 digits) but I surmise there must be a better  
> way to do it.
> So far, I have been changing them manually, but this task make the  
> whole thing terribly slow and inneficient.
> Any ideas are appreciated.
> Thanks.

What do you really want to know? Some prediction for anything? Or just 
the time t when 5 variables are changing between t-1 and t?
If the latter, calculate first order differences and check for t where 
all 5 first order differences are not equal to zero.

Uwe Ligges





> Cuanto mas grande son, mas da?o hacen. Postulado de Perkin.
> ------------------------------
> Jes?s Guillermo Andrade (Abg.)
> Gerente de Litigios y Corporativo. EDM. AC. API.
> Andrade & Moreno S.C. (http://amlegal.wordpress.com/)
> 
> 
> 	[[alternative HTML version deleted]]
> 
> 
> 
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