FUNCTION: FreeAdd - sum of two elements of the free algebra

CALLING SEQUENCE:

FreeAdd(e_1, e_2)

FREE[FreeAdd](e_1, e_2)

PARAMETERS:

e_1, e_2 = any elements of the free algebra

SYNOPSIS:

• The FreeAdd function adds two elements of the free algebra. It corresponds to the usual operation `+` but the function normalizes the result, by essentially collecting coefficients.

• One can use instead the operator &~+.

• Whenever there is a conflict between the function name FreeAdd and another name used in the same session, use the long form FREE['FreeAdd'].

EXAMPLES:

> with(FREE):
> a:=q + u/t*w[2,1,1]:
> b:=t - w[1,2,2]:
> FreeAdd(a, b);
 
                                              u w[2, 1, 1]
                   (q + t) w[] - w[1, 2, 2] + ------------
                                                    t
 
> a &~+ b;
 
                                              u w[2, 1, 1]
                   (q + t) w[] - w[1, 2, 2] + ------------
                                                    t