Difference between revisions of "ApCoCoA-1:NC.NR"

From ApCoCoAWiki
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</itemize>
 
</itemize>
 
<example>
 
<example>
NC.SetX(<quotes>abc</quotes>);
+
USE QQ[x[1..2],y[1..2]];
NC.RingEnv();
+
NC.SetOrdering("LLEX");
Coefficient ring : Q
+
F:= [[x[1],y[1],x[2]^2], [-9y[2],x[1]^2,x[2]^3],[5]]; -- x[1]y[1]x[2]^2-9y[2]x[1]^2x[2]^3+5
Alphabet : abc
+
G1:= [[y[1],x[2]^2], [y[2],x[2]^2]]; -- y[1]x[2]^2+y[2]x[2]^2
Ordering : LLEX
+
G2:= [[x[1],y[1]],[x[2]]]; -- x[1]y[1]+x[2]
-------------------------------
+
NC.NR(F,[G1,G2]);
F:=[[1,<quotes>ab</quotes>],[1,<quotes>aca</quotes>],[1,<quotes>bb</quotes>],[1,<quotes>bab</quotes>],[1,<quotes></quotes>]];
+
 
F1 := [[1,<quotes>a</quotes>],[1,<quotes>c</quotes>]];
+
[[-9y[2], x[1]^2, x[2]^3], [-x[1], y[2], x[2]^2], [5]]
F2 := [[1,<quotes>b</quotes>],[1,<quotes>ba</quotes>]];
 
G:=[F1,F2];
 
NC.NR(F,G);
 
[[1, <quotes>bcb</quotes>], [-1, <quotes>ccc</quotes>], [-1, <quotes>bb</quotes>], [1, <quotes>cb</quotes>], [-1, <quotes></quotes>]]
 
-------------------------------
 
NC.SetOrdering(<quotes>ELIM</quotes>);
 
NC.NR(F,G);
 
[[1, <quotes>bcb</quotes>], [-1, <quotes>bb</quotes>], [1, <quotes>cb</quotes>], [-1, <quotes>ccc</quotes>], [-1, <quotes></quotes>]]
 
 
-------------------------------
 
-------------------------------
 
</example>
 
</example>

Revision as of 17:59, 3 May 2013

NC.NR

Normal remainder of a polynomial with respect to a LIST of polynomials in a non-commutative polynomial ring.

Syntax

NC.NR(F:LIST, G:LIST):LIST

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 non-commutative polynomial ring (via the command Use) and word ordering (via the function NC.SetOrdering) before calling this function. The default word ordering is the length-lexicographic ordering ("LLEX"). For more information, please check the relevant commands and functions.

  • @param F: a non-commutative polynomial. Each polynomial is represented as a LIST of LISTs, and each element in every inner LIST involves only one indeterminate or none (a constant). For example, the polynomial f=2x[2]y[1]x[2]^2-9y[2]x[1]^2x[2]^3+5 is represented as F:=[[2x[1],y[1],x[2]^2], [-9y[2],x[1]^2,x[2]^3], [5]]. The zero polynomial 0 is represented as the empty LIST [].

  • @param G: a LIST of non-zero non-commutative polynomials.

  • @return: a LIST, which is the normal remainder of F with respect to G.

Example

USE QQ[x[1..2],y[1..2]];
NC.SetOrdering("LLEX");
F:= [[x[1],y[1],x[2]^2], [-9y[2],x[1]^2,x[2]^3],[5]]; -- x[1]y[1]x[2]^2-9y[2]x[1]^2x[2]^3+5
G1:= [[y[1],x[2]^2], [y[2],x[2]^2]]; -- y[1]x[2]^2+y[2]x[2]^2
G2:= [[x[1],y[1]],[x[2]]]; -- x[1]y[1]+x[2]
NC.NR(F,[G1,G2]);

[[-9y[2], x[1]^2, x[2]^3], [-x[1], y[2], x[2]^2], [5]]
-------------------------------

See also

Use

NC.SetOrdering

Introduction to CoCoAServer