What is the quickest way to extract the constant term from a Laurent polynomial in two variables? For example $x+1 +x^{-2}y+x/y$ has constant term $+1$.
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1$\begingroup$ Actual code is vastly preferable to something that cannot be copy-and-pasted. $\endgroup$– Daniel LichtblauCommented Mar 13, 2019 at 14:50
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1 Answer
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SeriesCoefficient[x + 1 + x^(-1) y + x/y, {x, 0, 0}, {y, 0, 0}]
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answered Mar 13, 2019 at 13:36
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$\begingroup$ Right, is this the quickest way? assume I will repeat this operation many many times $\endgroup$– jj_pCommented Mar 13, 2019 at 13:40
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1$\begingroup$ @jj_p: at worst, it should be not too inefficient. You don't mention how complicated your Laurent series can get. $\endgroup$ Commented Mar 13, 2019 at 13:47