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CoeffListWRT --
list of coefficients of a polynomial wrt an indet
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CoeffListWRT(F: RINGELEM, X: RINGELEM): LIST of RINGELEM |
This function returns the list of the coefficients of
F seen as a univariate
polynomial in
X, an indeterminate or a list of indeterminates
(with respect to (WRT)
X).
All entries in the returned list are RingElems belonging to
RingOf(F).
NOTE: the returned list is
reversed from the CoCoA-4 analogue
Coefficients(F,X) thus to re-use old code you should call
reversed(CoeffListWRT(F,X)).
/**/ use R ::= QQ[x,y,z];
/**/ F := 5*y^2 + (3*x^2-x)*y;
/**/ L := CoeffListWRT(F, y); Print L;
[0, 3*x^2 -x, 5]
/**/ F = sum([L[d+1]*y^d | d in 0..(len(L)-1)]);
true
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