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Call: ELECTRIC_FIELD


coordinates

This procedure accepts input arguments of types Number and Matrix.

If at least one of the input arguments x and y is of type Matrix, then all output arguments are of type Matrix, with the dimensions of the first input argument of type Matrix. If one input argument is of type Number and the other of type Matrix, then the Number type argument is "expanded" to become a Matrix filled uniformly with the value of the Number.

The coordinates system expected by ELECTRIC_FIELD is the internal frame. If you describe your cell in Cartesian coordinates, then the internal frame is simply the Cartesian coordinate system. If polar coordinates are used however, then you should supply the following parameters:

for x: log(r)
for y: phi, in radians

These mappings can be performed with the POLAR_TO_INTERNAL procedure.


field

The field is returned in internal coordinates. The internal coordinates system is Cartesian when the cell is described in Cartesian coordinates, but when you describe the cell in polar coordinates, you've to apply the following mapping:
Er = Ex/r
Ephi = Ey/r
Ez is invariant

status

Indicates where the point is located. If only scalar arguments are used as coordinates, then the status is returned in the form of a string. If at least one coordinate is a Matrix, then a matrix filled with numeric location codes is returned.

Status Location string Numeric
In a material Inside the mesh, but not in a drift medium -5
In an X wire Inside a wire of type X > 0
Normal In the active part of the cell 0
Outside mesh Not in any mesh triangle or tetrahedron -6
Outside plane On the side of a plane where no wires are -4 to -1
Unknown potential Unknown potential type (shouldn't occur) -10
Unknown Other cases (shouldn't occur) other


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Formatted on 0108-03- at 04:26.