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VectorInWidth -- the class of all elements of a free OI-module

Description

An element of a free OI-module $\mathbf{F}$ is defined to be an element of $\mathbf{F}_n$ for some integer $n\geq0$. Such an element is implemented as a VectorInWidth object. One typically makes VectorInWidth objects by defining a FreeOIModule object, calling installGeneratorsInWidth, and then manipulating the generators; see below for an example.

i1 : P = makePolynomialOIAlgebra(2, x, QQ);
i2 : F = makeFreeOIModule(e, {1,1}, P);
i3 : installGeneratorsInWidth(F, 2);
i4 : b = x_(1,1)*e_(2,{1},1)+x_(2,1)*e_(2,{1},2)

o4 = x   e        + x   e
      1,1 2,{1},1    2,1 2,{1},2

                                 4
o4 : (QQ[x   , x   , x   , x   ])  in width 2
          2,2   2,1   1,2   1,1
i5 : instance(b, VectorInWidth)

o5 = true

Methods that use an object of class VectorInWidth :

For the programmer

The object VectorInWidth is a type, with ancestor classes HashTable < Thing.