Drawing Graphs

Drawing Graphs

Graphs can be visualized by using either GraphPlot or rendering to .dot files (which can be viewed using xdot).

GraphPlot

GraphPlot plotting is available if GraphPlot is imported before DFG is imported. Install GraphPlot using the following command:

using Pkg
Pkg.add("GraphPlot")

Then bring GraphPlot in before DFG:

using GraphPlot
using DistributedFactorGraphs

Any factor graph can then be drawn by calling dfgplot:

using Cairo # hide
# Construct graph using IIF
using IncrementalInference
# Create graph
dfg = LightDFG{SolverParams}(solverParams=SolverParams())
v1 = addVariable!(dfg, :x0, ContinuousScalar, tags = [:POSE], solvable=1)
v2 = addVariable!(dfg, :x1, ContinuousScalar, tags = [:POSE], solvable=1)
v3 = addVariable!(dfg, :l0, ContinuousScalar, tags = [:LANDMARK], solvable=1)
prior = addFactor!(dfg, [:x0], Prior(Normal(0,1)))
f1 = addFactor!(dfg, [:x0; :x1], LinearConditional(Normal(50.0,2.0)), solvable=1)
f1 = addFactor!(dfg, [:l0; :x0], LinearConditional(Normal(40.0,5.0)), solvable=1)
f1 = addFactor!(dfg, [:l0; :x1], LinearConditional(Normal(-10.0,5.0)), solvable=1)

# Plot graph
dfgplot(dfg)

Rendering GraphPlot to PDF

The graph can be rendered to PDF, SVG or JPG in the following way by including compose:

using Compose
# lets add another variable and factor and plot it
dfg.solverParams.graphinit = false # hide
addVariable!(dfg, :x2, ContinuousScalar);
addFactor!(dfg, [:x1; :x2], LinearConditional(Normal(50.0,2.0)));
# Save to SVG
draw(SVG("graph.svg", 10cm, 10cm), dfgplot(dfg));
nothing # hide

More Information

More information at GraphPlot.jl

Dot Files

Dot files are a standard format for visualizing graphs and applications such as xdot are available to view the files. Dot plotting does not require GraphPlot and can be drawn by either:

using DistributedFactorGraphs
# Construct graph using IIF
using IncrementalInference
# Create graph
dfg = LightDFG{SolverParams}(solverParams=SolverParams())
v1 = addVariable!(dfg, :x0, ContinuousScalar, tags = [:POSE], solvable=1)
v2 = addVariable!(dfg, :x1, ContinuousScalar, tags = [:POSE], solvable=1)
v3 = addVariable!(dfg, :l0, ContinuousScalar, tags = [:LANDMARK], solvable=1)
prior = addFactor!(dfg, [:x0], Prior(Normal(0,1)))
f1 = addFactor!(dfg, [:x0; :x1], LinearConditional(Normal(50.0,2.0)), solvable=1)
f1 = addFactor!(dfg, [:l0; :x0], LinearConditional(Normal(40.0,5.0)), solvable=1)
f1 = addFactor!(dfg, [:l0; :x1], LinearConditional(Normal(-10.0,5.0)), solvable=1)
# Save to dot file
toDotFile(dfg, "/tmp/test.dot")
# Open with xdot
# run(`xdot /tmp/test.dot`)
# nothing # hide