This is a thin element which definition is:

Element name,	1st number,	2nd number,	3rd number
PSEUDOOCT,	k1 [m^{-4}],	half horizontal beam pipe [m],	half vertical beam pipe [m]

it creates the nonlinear kick

Delta x'  = k1 (x^3 + 3 y^2 x)
Delta y'  = -k1 (y^3 + 3 x^2 y)

used for the fringe field of the quadrupoles. The coefficient k1 it is equal to

                                         k10/(12 a)

where:
               k10  = strength of the quadrupole ;
               a    = half aperture of the quadrupole

The data of this element are stored in the matrix alat(n,m). The first index in alat identifies the lattice element as found in the sequence of elements loaded from the lattice file. The number of elements is NELMAX. In the variable alength is stored the lattice length.

alat(n,1) =	//
alat(n,2) =	10 ( number coding the type of element) ;
alat(n,3) =	longitudinal coordinate at the enter face of the n-th lattice element;
alat(n,4) =	longitudinal coordinate at the exit face of the n-th lattice element;
alat(n,5) =	k10 [m^{-4}];
alat(n,6) =	//
alat(n,7) =	//
alat(n,8) =	//
alat(n,9) =	//
alat(n,10) =	//
alat(n,11) =	length of the n-th element [m];
alat(n,12) =	half horizontal beam pipe [m];
alat(n,13) =	half vertical beam pipe [m];