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The leading coefficient of a non-zero polynomial in a free monoid ring.
NCo.LC(F:LIST):INT or RAT
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Please note: The function(s) explained on this page is/are using the
ApCoCoAServer. You will have to start the ApCoCoAServer in order to use it/them.
Please set ring environment
coefficient field K,
alphabet (or set of indeterminates)
X and
ordering via the functions
NCo.SetFp,
NCo.SetX and
NCo.SetOrdering, respectively, before using this function. The default coefficient field is
Q, and the default ordering is the length-lexicographic ordering ("LLEX"). For more information, please check the relevant functions.
- @param F: a non-zero polynomial in K. Each polynomial is represented as a LIST of monomials, which are LISTs of the form [C, W] where W is a word in and C is the coefficient of W. For example, the polynomial f=xy-y+1 is represented as F:=[[1,"xy"], [-1, "y"], [1,""]]. The zero polynomial 0 is represented as the empty LIST [].
- @return: a INT or RAT, which represents the leading coefficient of F with respect to the current word ordering. If F=0, the function returns 0.
NCo.SetX("abc");
F:=[[1,"ab"],[2,"aa"],[3,"bb"],[4,"bab"]];
NCo.SetOrdering("ELIM");
NCo.LC(F);
2
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NCo.SetOrdering("LLEX");
NCo.LC(F);
4
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NCo.LC([]); -- 0 polynomial
0
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