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 Author Comment/Response Eric Harley 10/12/05 08:25am Well, I guess I answered my own question. I'm posting what I have come up with in case it's useful for anyone else. I chose to use this approach (using the Exponent[] function) because it allows the resulting function to be much more flexible than I could figure out how to do with my own pattern matching. It can easily be used with specific variables, it includes stuff in the denominator of fractions, etc. Clear[polyOrder]; polyOrder = Function[{poly, varlist, ord}, Block[{termsList, orderList, selTerms}, termsList = List @@ poly; orderList = Exponent[#, varlist, List] & /@ termsList; orderList = Map[Flatten, orderList, 2]; orderList = Apply[Plus, orderList, 2]; termsList = Transpose[{termsList, orderList}]; selTerms = Select[termsList, #〚2〛 ≤ ord &]; Plus @@ (#〚1〛 & /@ selTerms) ] ]; Note that poly isn't the direct result of the Series[] function in the question. You should do //Normal//Expand on it to get rid of the O[] terms and all the factoring. varlist should always be in list form, like {x} or {x,y,z}. ord is just a number, the order of the product of the variables in varlist for any given term. URL: ,

 Subject (listing for 'Power series in multiple variables') Author Date Posted Power series in multiple variables Eric Harley 10/11/05 11:34am Re: Power series in multiple variables Eric Harley 10/12/05 08:25am Re: Power series in multiple variables Eric Harley 10/14/05 09:19am Re: Power series in multiple variables Carbaboran 01/25/12 06:53am
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