class JAS::WordPolyIdeal

Represents a JAS non-commutative polynomial ideal.

Methods for two-sided Groebner bases and others. Note: watch your step: check that jruby does not reorder multiplication.

Attributes

ideal[R]

the Java word polynomial ring, word polynomial list, word ideal

list[R]

the Java word polynomial ring, word polynomial list, word ideal

ring[R]

the Java word polynomial ring, word polynomial list, word ideal

Public Class Methods

new(ring,ringstr="",list=nil) click to toggle source

Constructor for an ideal in a non-commutative polynomial ring.

     # File examples/jas.rb
5833 def initialize(ring,ringstr="",list=nil)
5834     @ring = ring;
5835     if list == nil
5836        #raise "parse of non-commutative polynomials not implemented"
5837        sr = StringReader.new( ringstr );
5838        tok = GenPolynomialTokenizer.new(sr);
5839        @list = tok.nextWordPolynomialList(ring.ring);
5840        @ideal = WordIdeal.new(ring.ring, @list);
5841     else
5842        if list.is_a? WordIdeal
5843           @list = list.list;
5844           @ideal = list;
5845        else 
5846           @list = rbarray2arraylist(list, rec=1);
5847           @ideal = WordIdeal.new(ring.ring, @list);
5848        end
5849     end
5850 end

Public Instance Methods

<=>(other) click to toggle source

Compare two ideals.

     # File examples/jas.rb
5933 def <=>(other)
5934     s = @ideal; 
5935     o = other.ideal; 
5936     return s.compareTo(o); 
5937 end

==(other) click to toggle source

Test if two ideals are equal.

     # File examples/jas.rb
5942 def ==(other)
5943     if not other.is_a? WordPolyIdeal
5944        return false;
5945     end
5946     s = @ideal; 
5947     t = other.ideal; 
5948     return s.equals(t); 
5949 end

GB() click to toggle source

Compute a two-sided Groebner base.

     # File examples/jas.rb
5864 def GB()
5865     return twosidedGB();
5866 end

isGB() click to toggle source

Test if this is a two-sided Groebner base.

     # File examples/jas.rb
5900 def isGB()
5901     return isTwosidedGB();
5902 end

isTwosidedGB() click to toggle source

Test if this is a two-sided Groebner base.

     # File examples/jas.rb
5907 def isTwosidedGB()
5908     cofac = @ring.ring.coFac;
5909     kind = "";
5910     t = System.currentTimeMillis();
5911     if cofac.isField() or not cofac.isCommutative()
5912        b = @ideal.isGB();
5913        kind = "field|nocom"
5914     else 
5915         if cofac.is_a? GenPolynomialRing
5916            ff = @ideal.list;
5917            b = WordGroebnerBasePseudoRecSeq.new(cofac).isGB(ff);
5918            kind = "pseudoRec"
5919         else
5920            ff = @ideal.list;
5921            b = WordGroebnerBasePseudoSeq.new(cofac).isGB(ff);
5922            kind = "pseudo"
5923         end
5924     end
5925     t = System.currentTimeMillis() - t;
5926     puts "isTwosidedGB(#{kind}) = #{b} executed in #{t} ms\n"; 
5927     return b;
5928 end

sum(other) click to toggle source

Compute the sum of this and the ideal.

     # File examples/jas.rb
5954 def sum(other)
5955     s = @ideal; 
5956     t = other.ideal; 
5957     nn = s.sum( t );
5958     return WordPolyIdeal.new(@ring,"",nn);
5959 end

to_s() click to toggle source

Create a string representation.

     # File examples/jas.rb
5855 def to_s()
5856     # return "( " + @list.map{ |e| e.toScript() }.join(", ") + " )";
5857     #return "( " + @list.map{ |e| e.toScript() }.join(",\n") + " )";
5858     return @ideal.toScript();
5859 end

twosidedGB() click to toggle source

Compute a two-sided Groebner base.

     # File examples/jas.rb
5871 def twosidedGB()
5872     cofac = @ring.ring.coFac;
5873     kind = "";
5874     t = System.currentTimeMillis();
5875     if cofac.isField() or not cofac.isCommutative()
5876        gg = @ideal.GB();
5877        kind = "field|nocom"
5878     else 
5879         #puts "is ring: " + str(cofac.is_a? GenPolynomialRing)
5880         if cofac.is_a? GenPolynomialRing #and cofac.isCommutative()
5881            ff = @ideal.list;
5882            fg = WordGroebnerBasePseudoRecSeq.new(cofac).GB(ff);
5883            @ideal = WordIdeal.new(ring.ring, fg);
5884            kind = "pseudoRec"
5885         else
5886            ff = @ideal.list;
5887            fg = WordGroebnerBasePseudoSeq.new(cofac).GB(ff);
5888            @ideal = WordIdeal.new(ring.ring, fg);
5889            kind = "pseudo"
5890         end
5891     end
5892     t = System.currentTimeMillis() - t;
5893     puts "executed(#{kind}) twosidedGB in #{t} ms\n"; 
5894     return self;
5895 end