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list of coefficients of a polynomial wrt and indet
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.
All entries in the returned list are RingElems belonging to
RingOf(F)
.
Note that 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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