			function dBZA = dBZA(l,a,b,z) % % function dBZA = dBZA(l,a,b,z) % % Returns the FIRST derivative of the on-axis magnetic field % associated to a rectangular coil centered on z=0 % in which a unit current density 1/(ab) [A/m^2] is flowing % The analytic formula is exact on the axis and is based on % Martin Wilson: 'Superconducting Magnets', Oxford Science publications, 1990, p20. % plus some cumbersome derivation. % % % Version: 1.0 J.-P. Hogge Sept 25, 2001 % % a : Minor radius % b : major radius % l : longitudinal extent of the coil (from -l/2 to +l/2) % z : a one-dimensional array mu0 = 4pi1e-7; T1 = T(l,a,b,-z); T2 = T(l,a,b,z); T3 = T(l,a,a,-z); T4 = T(l,a,a,z); T5 = (T1-b/a).^2; T6 = (T2-b/a).^2; T7 = (T3-1).^2; T8 = (T4-1).^2; dBZA = mu0/2 ( ... ((T1 .* sqrt(T5) -T3.sqrt(T7))./(4a^2 * T1.T3.sqrt(T5).sqrt(T7))).(l-2z).^2 ... - ((T2 . sqrt(T6) -T4.sqrt(T8))./(4a^2 * T2.T4.sqrt(T6).sqrt(T8))).(l+2*z).^2 ... - log(T1./T3) ... + log(T2./T4) ... ); return

fennecs/matlab/Magnetic_Field_GLS_2020/librairie/dBZA.m
95267fe0c24bgeom_test

dBZA.m
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