Difference between revisions of "ApCoCoA-1:NCo.BLC"

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</syntax>
 
</syntax>
 
<description>
 
<description>
Please set ring environment <em>alphabet</em> (or set of indeterminates) <tt>X</tt> and <em>word ordering</em> via the functions <ref>ApCoCoA-1:NCo.SetX|NCo.SetX</ref> and <ref>ApCoCoA-1:NCo.SetOrdering|NCo.SetOrdering</ref>, respectively, before calling this function. The default ordering is the length-lexicographic ordering (<quotes>LLEX</quotes>). For more information, please check the relevant functions.
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Please set ring environment <em>alphabet</em> (or set of indeterminates) <tt>X</tt> and <em>word ordering</em> via the functions <ref>ApCoCoA-1:NCo.SetX|NCo.SetX</ref> and <ref>ApCoCoA-1:NCo.SetOrdering|NCo.SetOrdering</ref>, respectively, before calling this function. The default ordering is the length-lexicographic ordering ("LLEX"). For more information, please check the relevant functions.
 
<itemize>
 
<itemize>
<item>@param <em>F:</em> a non-zero polynomial in the free monoid ring <tt>F_{2}&lt;X&gt;</tt>. Each polynomial is represented as a LIST of words (or terms) in <tt>&lt;X&gt;</tt>. Each word is represented as a STRING. For example, <tt>xy^2x</tt> is represented as <quotes>xyyx</quotes>, and the identity is represented as the empty string <quotes></quotes>. Thus, the polynomial <tt>f=xy-y+1</tt> is represented as F:=[<quotes>xy</quotes>, <quotes>y</quotes>, <quotes></quotes>]. The zero polynomial <tt>0</tt> is represented as the empty LIST [].</item>
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<item>@param <em>F:</em> a non-zero polynomial in the free monoid ring <tt>F_{2}&lt;X&gt;</tt>. Each polynomial is represented as a LIST of words (or terms) in <tt>&lt;X&gt;</tt>. Each word is represented as a STRING. For example, <tt>xy^2x</tt> is represented as "xyyx", and the identity is represented as the empty string "". Thus, the polynomial <tt>f=xy-y+1</tt> is represented as F:=["xy", "y", ""]. The zero polynomial <tt>0</tt> is represented as the empty LIST [].</item>
 
<item>@return: a INT which represents the leading coefficient of F with respect to the current word ordering. Actually, the function returns 0 if F=0 and returns 1 otherwise.</item>
 
<item>@return: a INT which represents the leading coefficient of F with respect to the current word ordering. Actually, the function returns 0 if F=0 and returns 1 otherwise.</item>
 
</itemize>
 
</itemize>
 
<example>
 
<example>
NCo.SetX(<quotes>xX</quotes>);
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NCo.SetX("xX");
NCo.SetOrdering(<quotes>LLEX</quotes>);
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NCo.SetOrdering("LLEX");
F1:=[<quotes>xX</quotes>,<quotes></quotes>];
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F1:=["xX",""];
 
NCo.BLC(F1);
 
NCo.BLC(F1);
 
1
 
1

Latest revision as of 13:37, 29 October 2020

This article is about a function from ApCoCoA-1.

NCo.BLC

The leading coefficient of a non-zero polynomial in a free monoid ring over the binary field F_{2}={0,1}.

Syntax

NCo.BLC(F:LIST):INT

Description

Please set ring environment alphabet (or set of indeterminates) X and word ordering via the functions NCo.SetX and NCo.SetOrdering, respectively, before calling this function. The default ordering is the length-lexicographic ordering ("LLEX"). For more information, please check the relevant functions.

  • @param F: a non-zero polynomial in the free monoid ring F_{2}<X>. Each polynomial is represented as a LIST of words (or terms) in <X>. Each word is represented as a STRING. For example, xy^2x is represented as "xyyx", and the identity is represented as the empty string "". Thus, the polynomial f=xy-y+1 is represented as F:=["xy", "y", ""]. The zero polynomial 0 is represented as the empty LIST [].

  • @return: a INT which represents the leading coefficient of F with respect to the current word ordering. Actually, the function returns 0 if F=0 and returns 1 otherwise.

Example

NCo.SetX("xX");
NCo.SetOrdering("LLEX");
F1:=["xX",""];
NCo.BLC(F1);
1
-------------------------------
NCo.BLC([]);
0
-------------------------------

See also

NCo.SetOrdering

NCo.SetX

Introduction to CoCoAServer