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    Mathematica Streamlining Replace in Mathematica 8

    Hi and thanks for your answer. Ok, i just realize i have been too vague. Acutally my expressions are of the type MP[X,a_1]...MP[X,a_{2n}] where MP is the Minkowski scalar product. Some of the a_n might be the some. This can be replaced in my case (under an integral over X) by...
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    Mathematica Streamlining Replace in Mathematica 8

    Hi guys, i have expressions of the type (X*a)(X*b). I want replace this by X^2(a*b). So i tried building a block which does nothing but %//.(X*a_)(X*b_)->X^2(a*b). However, this works only if a is distinct from b. If a and b are equal if HAVE to use the replacement command...
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    Mathematica [Mathematica] How to calculate residues if poles not simple?

    Hi again! Hm, you are right. What I forgot to write, is that I (or precisely the guys in the paper) am/are doing a Taylor expansion of the solution the zeros of the denominator in epsilon and evaluate the residues at the Taylor expanded expression. In that sense "my" epsilon (after Taylor...
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    Mathematica [Mathematica] How to calculate residues if poles not simple?

    Hi, thanks for the answer :) The poles of the denominator are located at x^\pm= \frac{B \pm \sqrt{d} \mp i \epsilon }{A} and i want to evaluate the residues at x^- . So i type into Mathematica Residue[...
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    Mathematica [Mathematica] How to calculate residues if poles not simple?

    Thanks for the reply! Ok, if I enter a function (a similar one, to be more specific but the core question remains) in its original form \frac{(Q*X+q*x)}{((x-B/A)^2-(B^2-AC)/A^2+i\frac{\epsilon}{A})^3} Mathematica gives me as the residue zero. But I know (from calculating it...
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    Mathematica [Mathematica] How to calculate residues if poles not simple?

    Hey guys, i have the following situation: I have a function which looks like \frac{(a+bx)^3}{(x-y)^6(x-z)^6} As one can easily see this function has poles at y and z of order 6. Now, I know how to calculate the residue of this function for instance at y, but how do I implement this into...
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