boundary_conditions

Functions for applying boundary conditions

enforce boundary conditions in vpa and z on the evolved pdf; also enforce boundary conditions in z on all separately evolved velocity space moments of the pdf

Set up an initial condition that tries to be smoothly compatible with the sheath boundary condition for ions, by setting f(±(v_parallel-u0)<0) where u0=0 at the sheath boundaries and for z<0 increases linearly to u0=vpa.L at z=0, while for z>0 increases from u0=-vpa.L at z=0 to zero at the z=z.L/2 sheath.

To be applied to 'full-f' distribution function on vparallel grid (not wparallel grid).

enforce boundary conditions on neutral particle distribution function

enforce the wall boundary condition on neutrals; i.e., the incoming flux of neutrals equals the sum of the ion/neutral outgoing fluxes

enforce boundary conditions on neutral particle f in z

enforce boundary conditions on f in r

enforce zero boundary condition at vperp -> infinity

enforce boundary conditions on ion particle f in z

enforce the z boundary condition on the evolved velocity space moments of f

enforce a zero incoming BC in z for given species pdf at each radial location

skip_f_electron_bc_points_in_Jacobian(iz, ivperp, ivpa, z, vperp, vpa)

This function returns true when the grid point specified by iz, ivperp, ivpa would be set by the boundary conditions on the electron distribution function. When this happens, the corresponding row should be skipped when adding contributions to the Jacobian matrix, so that the row remains the same as a row of the identity matrix, so that the Jacobian matrix does not modify those points. Returns false otherwise.

create an array of dz/dt values corresponding to the given vpagrid values