(* MAS Non-commutative Definition Module. *)

DEFINITION MODULE MASNC;


FROM MASSTOR IMPORT LIST;


PROCEDURE DINPPR(T,A,B: LIST): LIST; 
(*Distributive polynomial non commutative product.
A and B are distributive polynomials. T is a table
of distributive polynomials specifying the non commutative
relations. C=A*B, the non commutative product of A and B.
The table T may be modified. *)


PROCEDURE DINPTL(T,EL,FL: LIST;  VAR C,EP,FP: LIST); 
(*Distributive polynomial non commutative product table lookup.
e and f are exponent vectors. T is a table
of distributive polynomials specifying the non commutative
relations. C is the non-commutative product of x**es and x**fs.
ep and fp are exponent vectors with es+ep=e and fs+fp=f.
If e=es or f=fs then ep=() or fp=(). *)


PROCEDURE DINPTU(T,EL,FL,C: LIST); 
(*Distributive polynomial non commutative product table update.
e and f are exponent vectors. T is a table
of distributive polynomials specifying the non commutative
relations. C is a distributive rational polynomial. The relation
e * f = C is added to T. T is modified. *)


PROCEDURE DINPEX(T,A,NL: LIST): LIST; 
(*Distributive non commuting polynomial exponentiation. A is a
distributive rational polynomial, n is a non-negative beta-
integer. T is a table of non commuting relations.
B=A**n. 0**0 is by definition a polynomial in zero variables. *)


PROCEDURE DINLRD(V,T: LIST): LIST; 
(*Distributive non commuting polynomial list read. V is a
variable list. T is a table of non commuting relations.
A list of distributive non commuting polynomials
in r variables, where r=length(V), r ge 0, is read from
the input stream. Any blanks preceding A are skipped. *)


PROCEDURE DINPRD(V,T: LIST): LIST; 
(*Distributive non commuting polynomial read. V is a variable list.
T is a table on non commuting relations.
A distributive rational polynomial A in r variables, where
r=length(V), r ge 0, is read from the input stream. Any
blanks preceding A are skipped. *)


PROCEDURE EVZERO(RL: LIST): LIST; 
(*Exponent vector zero. U is an exponent vector of length r,
r ge 0 with all components zero. *)


END MASNC.