ApCoCoA-1:NCo.IsHomog

From ApCoCoAWiki
Revision as of 17:21, 25 April 2013 by Xiu (talk | contribs) (New page: <command> <title>NCo.IsHomog</title> <short_description> Check whether a polynomial or a list of polynomials is homogeneous in a free monoid ring. </short_description> <syntax> NCo.IsHomog...)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

NCo.IsHomog

Check whether a polynomial or a list of polynomials is homogeneous in a free monoid ring.

Syntax

NCo.IsHomog(F:LIST):BOOL

Description

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 calling the function. The default coefficient field is Q. The default ordering is length-lexicographic ordering ("LLEX"). For more information, please check the relevant functions.

  • @param F: a polynomial or a LIST of polynomials in K<X>. Each polynomial is represented as a LIST of monomials, which are pairs of the form [C, W] where W is a word in <X> 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 BOOL value which is True if F is homogeneous and False otherwise. Note that if F is a set of homogeneous polynomials, then F generates a homogeneous ideal. It is false contrarily.

Example

NCo.SetX(<quotes>xy</quotes>); 
F1 := [[1,<quotes>x</quotes>], [1,<quotes>y</quotes>]]; 
F2 := [[1,<quotes>xx</quotes>],[1,<quotes>xy</quotes>],[1,<quotes>x</quotes>]]; 
F := [F1,F2]; 
NCo.IsHomog(F);
False
-------------------------------
NCo.IsHomog(F1);
True
-------------------------------
NCo.IsHomog(F2);
False
-------------------------------

See also

NCo.SetFp

NCo.SetX

Introduction to CoCoAServer