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Re: Sum of powers of multiplied terms

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x = k1^2 k2^2 e^2 Sin[phi] + k3^2 e k4^2 Sin[theta];

Thread[{
  Range[Length[x]],
  Replace[Plus @@@ List @@ x, _^n_. -> n, {2}] - 1}]

{{1, 6}, {2, 5}}

@@ is Apply
@@@ is Apply to level 1
_. is Default

Bob Hanlon

---- Chelly <chelly85086@gmail.com> wrote: 

=============
I am new to Mathematica and need some help on the following:

I have a variable which has a sum of many sine terms as shown below:

x = k1^2 k2^2 e^2 Sin(phi) + k3^2 e k4^2 Sin(theta) +....

I'd like to create a table where the first element is the index of the list and the second element is the sum of the powers of the amplitude terms. In this case, I'd like it to be

{1,6},{2,5}

where the sum of powers of the first amplitude term is 2+2+2=6, and similarly for the second term it is 2+1+2=5

Thanks
Chelly

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Re: Sum of powers of multiplied terms Bob Hanlon <hanlonr@cox.net> - 2011-03-31 09:00 +0000

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