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 Coefficients

list of coefficients of a polynomial or vector
 Syntax
 ``` Coefficients(F:POLY or VECTOR):LIST Coefficients(F:POLY, X:INDET):LIST Coefficients(F:POLY, S:LIST):LIST ```

 Description
This function returns the coefficients of F. In the first form, a list of the (non-zero) coefficients is returned; the order being decreasing on the terms in F as determined by the term-ordering of the ring to which F belongs.

In the second form, the function views F as a polynomial in X, and returns a list of coefficients which are polynomials in the remaining variables; their order is decreasing in powers of X, and a zero value is given for those powers of X absent from F.

In the third form, the coefficients of the specified terms are returned; their order is determined by the list S.

 Example
 ``` Use R ::= QQ[x,y,z]; F := 3x^2y + 5y^3 - xy^5; Coefficients(F); [-1, 3, 5] ------------------------------- ScalarProduct(Coefficients(F), Support(F)) = F; TRUE ------------------------------- V := Vector(3x^2+y, x-5z^3); Coefficients(V); [-5, 3, 1, 1] ------------------------------- ScalarProduct(Coefficients(V), Support(V)) = V; TRUE ------------------------------- Coefficients(x^3z+xy+xz+y+2z, x); [z, 0, y + z, y + 2z] ------------------------------- F := (1 + 2x + 3y^4 + 5z^6)^7; Skeleton := [1, x^3, y^12, z^19, x^2*y^8*z^12]; Coefficients(F, Skeleton); [1, 280, 945, 0, 567000] ------------------------------- ```