&CELL: PERIODICITY

direction

The direction in which the cell is infinitely repeated. Can have one of the following 3 values:

Direction	Meaning	Coordinate system
`X`	Cell repeats in x	Cartesian
`Y`	Cell repeats in y	Cartesian
`Z`	Cell repeats in z	-
`PHI`	Axial periodicity around the origin	Polar or Tube

Repetition in r is not permitted because of the method used to calculate the potentials in cylindrical geometry.

Cylindrical geometries are handled via a conformal mapping onto a Cartesian coordinate system in which an r-periodicity would be equivalent to an x-periodicity with non-constant intervals. This is technically difficult to deal with. Contact the author if there is a genuine need for such a periodicity.

Periodicity in z is only allowed with neBEM field calculations, not in wire and planes chambers.

length

The length of one full period, expressed in cm for x and y periodicities and in degrees for periodicity in \φ.

REGULAR

Indicates that all periodic copies of the basic cell are identical.

This is the only type of periodicity permitted in cells constructed of wires and planes. This type of periodicity is recognised by neBEM.

[If periodicity is requested, then it will by default have this type of periodicity.]

MIRROR

Indicates that odd periodic copies of the basic cell are mirror images of even periodic copies.

This is the type of periodicity is not permitted in cells constructed of wires and planes. This type of periodicity is recognised by neBEM.

[If periodicity is requested, then it will by default be regular.]

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Formatted on 21/01/18 at 16:55.