Using a standard seed

Initial seeds in the form of line segments are supported. These seeds can be defined with the following parameters, where N refers to the number of seeds the user wants to define:

name	value	description
`seed_density`	N * real	Maximum density for the seed (in 1/m3)
`seed_rel_r0`	N * NDIM reals	relative start position (between 0 and 1)
`seed_rel_r1`	N * NDIM reals	relative end position (between 0 and 1)
`seed_charge_type`	N * integer	0 for neutral, 1 for positive ions, -1 for electrons
`seed_falloff`	N * string	Fall-off type for seed (sigmoid, gaussian, smoothstep, step, laser)
`seed_width`	N * real	Seed decay width (m)

Other settings that control the initial conditions are:

name	value	description
`background_density`	real	The background ion and electron density (1/m3)

Defining custom initial conditions

To define custom initial conditions, specify the following in your m_user.f90 file:

user_initial_conditions => my_init_cond

where my_init_cond is a routine (see m_user_methods::user_initial_conditions) that can modify the initial state in any way you like.

Finding the index of a species

To set the value of a particular species, first find its index with

i_species = af_find_cc_variable(tree, "species_name")

then you can for example set species density to zero (in 2D) with

box%cc(:, :, i_species) = 0.0_dp