CellsOnTop, CellsOnBottom, CellsOnLeft, CellsOnRight, EdgesOnTop, EdgesOnBottom, EdgesOnLeft, EdgesOnRight, VerticesOnTop, VerticesOnBotom, VerticesOnLeft, VerticesOnRight | Cellzilla2D Home |

Description

Needs["Cellzilla2D`"];

Return Value

Returns a list of cells, edges, or vertex numbers that lie on the left, right, top or bottom of an object, as defined by the outward projecting normal vector.

Options

Example

[ Download Example as Zipped Mathematica Notebook ]

Implementation Notes

In some cases (such as the example shown) some of the identifications may be counter-intuitive.

A vertex is on the left, right, top, or bottom of the tissue if (a) it is on the boundary and (b) the dot product of all the outward vectors returned by CellOutwardVector for that vertex and the canonical direction vector is positive. The canonical direction vectors are {0,1}, {0,-1}, {1,0}, {-1,0} for top, bottom, right, and left, respectively.

An edge is on the left, right, top, or bottom if either endpoint is on the left, right, top, or bottom of the tissue, respectively.

A cell is on the left, right, top, or bottom if any of its component edges are on the left, right, top or bottom of th tissue.

See Also