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cells -- return the cells of a cell complex as a hashtable whose keys are cell dimensions

Synopsis

Description

Given a cell complex, this function will return all the cells in that cell complex, index by dimension. The order of the cells in each dimension is arbitrary.

i1 : R = QQ[x,y,z];
 
i2 : vx = newSimplexCell({},x);
 
i3 : vy = newSimplexCell({},y);
 
i4 : vz = newSimplexCell({},z);
 
i5 : exy = newSimplexCell {vx,vy};
 
i6 : C = cellComplex(R,{exy,vz});
 
i7 : cells(C)

o7 = HashTable{0 => {Cell of dimension 0 with label y, Cell of dimension 0 with label z, Cell of dimension 0 with label x}}
               1 => {Cell of dimension 1 with label x*y}

o7 : HashTable
 
i8 : R = QQ;
 
i9 : P = convexHull matrix {{1,1,-1,-1},{1,-1,1,-1}};
 
i10 : C = cellComplex(R,P);
 
i11 : cells C

o11 = HashTable{0 => {Cell of dimension 0 with label 1, Cell of dimension 0 with label 1, Cell of dimension 0 with label 1, Cell of dimension 0 with label 1}}
                1 => {Cell of dimension 1 with label 1, Cell of dimension 1 with label 1, Cell of dimension 1 with label 1, Cell of dimension 1 with label 1}
                2 => {Cell of dimension 2 with label 1}

o11 : HashTable

See also

Ways to use cells :

For the programmer

The object cells is a method function.