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
6066 def initialize(ring,ringstr="",list=nil)
6067     @ring = ring;
6068     if list == nil
6069        #raise "parse of non-commutative polynomials not implemented"
6070        sr = StringReader.new( ringstr );
6071        tok = GenPolynomialTokenizer.new(sr);
6072        @list = tok.nextWordPolynomialList(ring.ring);
6073        @ideal = WordIdeal.new(ring.ring, @list);
6074     else
6075        if list.is_a? WordIdeal
6076           @list = list.list;
6077           @ideal = list;
6078        else 
6079           @list = rbarray2arraylist(list, rec=1);
6080           @ideal = WordIdeal.new(ring.ring, @list);
6081        end
6082     end
6083 end

Public Instance Methods

<=>(other) click to toggle source

Compare two ideals.

     # File examples/jas.rb
6166 def <=>(other)
6167     s = @ideal; 
6168     o = other.ideal; 
6169     return s.compareTo(o); 
6170 end

==(other) click to toggle source

Test if two ideals are equal.

     # File examples/jas.rb
6175 def ==(other)
6176     if not other.is_a? WordPolyIdeal
6177        return false;
6178     end
6179     s = @ideal; 
6180     t = other.ideal; 
6181     return s.equals(t); 
6182 end

GB() click to toggle source

Compute a two-sided Groebner base.

     # File examples/jas.rb
6097 def GB()
6098     return twosidedGB();
6099 end

isGB() click to toggle source

Test if this is a two-sided Groebner base.

     # File examples/jas.rb
6133 def isGB()
6134     return isTwosidedGB();
6135 end

isTwosidedGB() click to toggle source

Test if this is a two-sided Groebner base.

     # File examples/jas.rb
6140 def isTwosidedGB()
6141     cofac = @ring.ring.coFac;
6142     kind = "";
6143     t = System.currentTimeMillis();
6144     if cofac.isField() or not cofac.isCommutative()
6145        b = @ideal.isGB();
6146        kind = "field|nocom"
6147     else 
6148         if cofac.is_a? GenPolynomialRing
6149            ff = @ideal.list;
6150            b = WordGroebnerBasePseudoRecSeq.new(cofac).isGB(ff);
6151            kind = "pseudoRec"
6152         else
6153            ff = @ideal.list;
6154            b = WordGroebnerBasePseudoSeq.new(cofac).isGB(ff);
6155            kind = "pseudo"
6156         end
6157     end
6158     t = System.currentTimeMillis() - t;
6159     puts "isTwosidedGB(#{kind}) = #{b} executed in #{t} ms\n"; 
6160     return b;
6161 end

sum(other) click to toggle source

Compute the sum of this and the ideal.

     # File examples/jas.rb
6187 def sum(other)
6188     s = @ideal; 
6189     t = other.ideal; 
6190     nn = s.sum( t );
6191     return WordPolyIdeal.new(@ring,"",nn);
6192 end

to_s() click to toggle source

Create a string representation.

     # File examples/jas.rb
6088 def to_s()
6089     # return "( " + @list.map{ |e| e.toScript() }.join(", ") + " )";
6090     #return "( " + @list.map{ |e| e.toScript() }.join(",\n") + " )";
6091     return @ideal.toScript();
6092 end

twosidedGB() click to toggle source

Compute a two-sided Groebner base.

     # File examples/jas.rb
6104 def twosidedGB()
6105     cofac = @ring.ring.coFac;
6106     kind = "";
6107     t = System.currentTimeMillis();
6108     if cofac.isField() or not cofac.isCommutative()
6109        gg = @ideal.GB();
6110        kind = "field|nocom"
6111     else 
6112         #puts "is ring: " + str(cofac.is_a? GenPolynomialRing)
6113         if cofac.is_a? GenPolynomialRing #and cofac.isCommutative()
6114            ff = @ideal.list;
6115            fg = WordGroebnerBasePseudoRecSeq.new(cofac).GB(ff);
6116            @ideal = WordIdeal.new(ring.ring, fg);
6117            kind = "pseudoRec"
6118         else
6119            ff = @ideal.list;
6120            fg = WordGroebnerBasePseudoSeq.new(cofac).GB(ff);
6121            @ideal = WordIdeal.new(ring.ring, fg);
6122            kind = "pseudo"
6123         end
6124     end
6125     t = System.currentTimeMillis() - t;
6126     puts "executed(#{kind}) twosidedGB in #{t} ms\n"; 
6127     return self;
6128 end