QFunctionTools(C, L)

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• C: Ring
• L: UnivariateLaurentSeriesCategory C

QFunctionTools allows to create a series from another series.

choose: (Integer -> Integer , L, Integer ) -> L

choose(f, x, n0) returns the power series z whose n-th coefficient is the f(n)-th coefficient of x, i.e. coefficient(z, n) = coefficient(x, f n) for all n>=n0. Start with n=n0, i.e. the order of the result will be n0. choose(f, x, n0) = chooseAndMap(c+->c, f, x, n0)

chooseAndMap: (C -> C, Integer -> Integer , L, Integer ) -> L

chooseAndMap(g, f, x, n0) returns the power series z whose n-th coefficient is the f(n)-th coefficient of x after application of g, i.e. coefficient(z, n) = g(coefficient(x, f n)) for all n>=n0. Start with n=n0, i.e. the order of the result will be n0.