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newCell -- creates a new cell



This function creates a new cell, to be added to a cell complex, if given a list of cells without any orientation information, it attempts to infer the orientation.

If given an empty list for the boundary, the function creates a 0-cell (a vertex).

If not given a label, and the labels on the boundary are monomials or monomial ideals from the same ring, then the label is the lcm of the labels of the boundary.

If the dimension cannot be directly inferred from the boundary, CellDimension can be used to specify the true dimension

i1 : R = QQ[x,y]

o1 = R

o1 : PolynomialRing
i2 : a = newCell({},x);
i3 : b = newCell({},y);
i4 : c1 = newCell {(a,1),(a,-1)};
i5 : c2 = newCell {a,a};
i6 : c3 = newCell {a,b};
i7 : C = cellComplex(R,{c1,c2,c3});


This function does not check that there is a valid map from the boundary of an n-cell to the given boundary. It only checks that the boundary forms a cycle in homology.

See also

Ways to use newCell :

For the programmer

The object newCell is a method function with options.