Graph Layout Live

Description

Layout the graph live on the canvas using a physics simulator.

Usage

graph_live_layout(
  g,
  spring_length = 30L,
  sping_coeff = 8e-04,
  gravity = -1.2,
  theta = 0.8,
  drag_coeff = 0.02,
  time_step = 20L,
  is_3d = TRUE
)
graph_layout_live(
  g,
  spring_length = 30L,
  sping_coeff = 8e-04,
  gravity = -1.2,
  theta = 0.8,
  drag_coeff = 0.02,
  time_step = 20L,
  is_3d = TRUE
)

Arguments

Argument	Description
`g`	An object of class `graph` as returned by `graph` or a `graph_proxy` as returned by a function of the same name.
`spring_length`	Used to compute Hook's law, default of `30` is generally ideal.
`sping_coeff`	Hook's law coefficient, where `1` is a solid spring.
`gravity`	Coulomb's law coefficient. It's used to repel nodes thus should be negative if positive nodes attract each other.
`theta`	Theta coefficient from Barnes Hut simulation, between `0` and `1` . The closer it's to `1` the more nodes the algorithm will have to go through. Setting it to one makes Barnes Hut simulation no different from brute-force forces calculation (each node is considered).
`drag_coeff`	Drag force coefficient. Used to slow down system, thus should be less than `1` . The closer it is to 0 the less tight system will be.
`time_step`	Default time step $dt$ for forces integration.
`is_3d`	Whether to plot in 3 dimensions or 2 dimensions.

Details

Calculates forces acting on each body and then deduces their position via Newton's law. There are three major forces in the system:

list("Spring force keeps connected nodes together via ", list(list("https://en.wikipedia.org/wiki/Hooke's_law"), list("Hooke's law")), ".")
list("Each body repels each other via ", list(list("https://en.wikipedia.org/wiki/Coulomb's_law"), list("Coulomb's law")), ".")
list("To guarantee we get to "stable" state the system has a drag force which slows entire simulation down.")

Body forces are calculated in $n*lg(n)$ time with help of Barnes-Hut algorithm. Euler method is then used to solve ordinary differential equation of Newton's law and get position of bodies.

Examples

data <- make_data(20)

graph(data) %>%
graph_layout_live(time_step = 5L)