Hi Richard,
I found kdelta and kdels in the tensor package. Can you tell me how can I
use the properties of kdelta like:
kdelta(i,i)=1
sum(kdelta(i,j)*f(i,k),i,1,n)=f(j,k)
etc
Thanks & Regards
Dileep
> Dileep:
> You have posted what appears to be the same question about 4 times,
> about how to use defrule to solve a problem for which it is not suited.
>
> As you repeat the question, you have not changed it,
> in spite of having received several suggestions to use a different
> approach.
>
> I wrote the defrule system in my PhD research. I am advising you
> not to use it. I suggested that you look at tensor manipulation and the
> Einstein summation convention. Robert Dodier made what
> seems to be a useful suggestion.
>
> Encoding your problem as sum(g(i,j)*d(j,k) etc. IS A BAD IDEA.
>
>
> I suggest encoding it as something like
> DileepForm([[d,i,j],[g,i,j]......], /* the product */
> [[j,1,n], [k, 1,m] ....]] /* the index sets*/
>
>
>
> Manipulate DileepForms, their products, sums, etc.
>
>
> If you really really need sum, then at the VERY END, convert
> DileepForm to Sums.
>
>
> And don't use defrule on products a*b*c ....*z or a+b+....+z.
> There is a message about "partitioning sums" that is intended to
> signal you: YOU ARE LIKELY TO LOSE.
>
> Good luck,
> RJF
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