Core

apply!(sys::ParticleSystem, action!::Function; self::Bool = false)

Calls either apply_unary! or apply_binary! according to the signature of action!. If self == true, then particle self-interaction for binary operator is allowed.

apply_binary!(sys::ParticleSystem, action!::Function)

Apply a binary operator action!(p::T, q::T, r::Float64) between any two neighbouring particles p, q in sys::ParticleSystem{T}. Value r is their mutual distance. This excludes particle pairs with distance greater than sys.h. This has linear complexity in number of particles and runs in parallel.

apply_unary!(sys::ParticleSystem, action!::Function)

Apply a unary operator action!(p::T) on every particle p in sys::ParticleSystem{T}. This has linear complexity in number of particles and runs in parallel.

assemble_matrix(sys::ParticleSystem, func::Function)::SparseMatrixCSC{Float64}

For given function func(p::T, q::T)::Float64 where T <: AbstractParticle, assemble a sparse matrix $\mathbb{A}$, such that

\[ A_{ij} = \text{func}(p_i, p_j, r_{ij}),\]

where $p_i$, $p_j$ are respectively the i-th and j-th particle in sys::ParticleSystem{T} and $r_{ij}$ is their mutual distance. This assumes that $A_{ij} = 0$ for $r_{ij} > h$.

assemble_vector(sys::ParticleSystem, func::Function)::Vector{Float64}

For given function func(q::T)::Float64 where T <: AbstractParticle, assemble a vector $\mathbf{v}$, such that

\[ v_i = \text{func}(p_i),\]

where $p_i$ is the i-th particle in sys::ParticleSystem{T}.

create_cell_list!(sys::ParticleSystem)

Create the cell list for given particle system sys. This function should be always called after updating positions. Without updated cell list, applying binary particle operators or assembling matrices will lead to incorrect results.

dist(p::AbstractParticle, q::AbstractParticle)::Float64

Computes the distance between any two particles.

sum(sys::ParticleSystem, func::Function, x::RealVector)::Float64

For given function func(p::T, q::T, r::Float64)::Float64 where T <: AbstractParticle and particle p it returns the sum

\[ \sum_{q \in \text{sys.particles}} \text{func}(p, q, r).\]

sum(sys::ParticleSystem, func::Function, x::RealVector)::Float64

For given function func(p::T, r::Float64)::Float64 where T <: AbstractParticle it returns the sum

\[ \sum_{p \in \text{sys.particles}} \text{func}(p, \sqrt{(p.x - x)^2 + (p.y - y)^2}).\]

This can be useful if one needs to compute SPH interpolation at a point which is not occupied by a particle.