Regular grid

A regular grid is a tessellation of n-dimensional Euclidean space by congruent parallelotopes (e.g.

Since the derivatives of field variables can be conveniently expressed as finite differences,[2] structured grids mainly appear in finite difference methods.

in 3D for some real numbers dx, dy, and dz representing the grid spacing.

An example of a rectilinear grid that is not regular appears on logarithmic scale graph paper.

(If the unit lengths are all equal, it is a tessellation of rhombi or rhombohedra.)