invalid subtraction operation during visualization

[zlaouar]

After running the simple test script below:

using LaserTag
using POMDPGifs
using QMDP
using Random
using ParticleFilters

rng = MersenneTwister(7)

m = gen_lasertag(rng=rng, robot_position_known=true)
policy = solve(QMDPSolver(verbose=true), m)
filter = SIRParticleFilter(m, 10000, rng=rng)

@show makegif(m, policy, filter, filename="out.gif", rng=rng)

I get the following:

[Iteration 1   ] residual:         10 | iteration runtime:      2.163 ms, (   0.00216 s total)
[Iteration 2   ] residual:        9.5 | iteration runtime:      2.230 ms, (   0.00439 s total)
[Iteration 3   ] residual:       9.02 | iteration runtime:      2.192 ms, (   0.00659 s total)
[Iteration 4   ] residual:       8.57 | iteration runtime:      2.192 ms, (   0.00878 s total)
[Iteration 5   ] residual:       6.92 | iteration runtime:      2.209 ms, (     0.011 s total)
[Iteration 6   ] residual:       6.58 | iteration runtime:      2.179 ms, (    0.0132 s total)
[Iteration 7   ] residual:       6.25 | iteration runtime:      2.212 ms, (    0.0154 s total)
[Iteration 8   ] residual:       5.94 | iteration runtime:      2.249 ms, (    0.0176 s total)
[Iteration 9   ] residual:       5.64 | iteration runtime:      2.207 ms, (    0.0198 s total)
[Iteration 10  ] residual:       5.36 | iteration runtime:      2.208 ms, (     0.022 s total)
[Iteration 11  ] residual:       5.09 | iteration runtime:      2.205 ms, (    0.0242 s total)
[Iteration 12  ] residual:       4.83 | iteration runtime:      2.230 ms, (    0.0265 s total)
[Iteration 13  ] residual:       4.59 | iteration runtime:      2.177 ms, (    0.0287 s total)
[Iteration 14  ] residual:        3.2 | iteration runtime:      2.213 ms, (    0.0309 s total)
[Iteration 15  ] residual:        2.9 | iteration runtime:      2.204 ms, (    0.0331 s total)
[Iteration 16  ] residual:       2.76 | iteration runtime:      2.441 ms, (    0.0355 s total)
[Iteration 17  ] residual:       2.62 | iteration runtime:      2.909 ms, (    0.0384 s total)
[Iteration 18  ] residual:     0.0508 | iteration runtime:      2.705 ms, (    0.0411 s total)
[Iteration 19  ] residual:    0.00966 | iteration runtime:      2.589 ms, (    0.0437 s total)
[Iteration 20  ] residual:    0.00734 | iteration runtime:      2.731 ms, (    0.0464 s total)
[Iteration 21  ] residual:    0.00558 | iteration runtime:      2.638 ms, (    0.0491 s total)
[Iteration 22  ] residual:    0.00424 | iteration runtime:      2.755 ms, (    0.0518 s total)
[Iteration 23  ] residual:    0.00322 | iteration runtime:      2.781 ms, (    0.0546 s total)
[Iteration 24  ] residual:    0.00245 | iteration runtime:      2.213 ms, (    0.0568 s total)
[Iteration 25  ] residual:    0.00186 | iteration runtime:      2.321 ms, (    0.0592 s total)
[Iteration 26  ] residual:    0.00141 | iteration runtime:      3.115 ms, (    0.0623 s total)
[Iteration 27  ] residual:    0.00108 | iteration runtime:      2.605 ms, (    0.0649 s total)
[Iteration 28  ] residual:   0.000817 | iteration runtime:      2.619 ms, (    0.0675 s total)
ERROR: MethodError: no method matching -(::StaticArraysCore.SVector{2, Int64}, ::Float64)
For element-wise subtraction, use broadcasting with dot syntax: array .- scalar
Closest candidates are:
  -(::Base.TwicePrecision, ::Number) at ~/Software/julia-1.7.2/share/julia/base/twiceprecision.jl:293
  -(::GeometryBasics.HyperRectangle{N, T}, ::Number) where {N, T} at ~/.julia/packages/GeometryBasics/6JxlJ/src/primitives/rectangles.jl:266
  -(::LinearAlgebra.UniformScaling, ::Number) at ~/Software/julia-1.7.2/share/julia/stdlib/v1.7/LinearAlgebra/src/uniformscaling.jl:147
  ...
Stacktrace:
 [1] show_meas(o::IOBuffer, s::LTState, obs::StaticArraysCore.MVector{8, Int64})
   @ LaserTag ~/.julia/packages/LaserTag/uG83u/src/visualization.jl:64
 [2] tikz_pic(v::LaserTagVis)
   @ LaserTag ~/.julia/packages/LaserTag/uG83u/src/visualization.jl:108
 [3] show(io::IOStream, mime::MIME{Symbol("image/png")}, v::LaserTagVis)
   @ LaserTag ~/.julia/packages/LaserTag/uG83u/src/visualization.jl:29
 [4] writeframe(filename::String, mime::MIME{Symbol("image/png")}, frame::LaserTagVis)
   @ Reel ~/.julia/packages/Reel/HdonC/src/Reel.jl:35
 [5] push!
   @ ~/.julia/packages/Reel/HdonC/src/Reel.jl:42 [inlined]
 [6] makegif(m::LaserTagPOMDP{DESPOTEmu, StaticArraysCore.MVector{8, Int64}}, hist::POMDPTools.Simulators.SimHistory{NamedTuple{(:s, :a, :sp, :o, :r, :info, :t, :action_info, :b, :bp, :update_info), Tuple{LTState, Int64, LTState, StaticArraysCore.MVector{8, Int64}, Float64, Nothing, Int64, Nothing, ParticleCollection{LTState}, ParticleCollection{LTState}, Nothing}}, Float64}; filename::String, spec::Nothing, show_progress::Bool, extra_initial::Bool, extra_final::Bool, render_kwargs::NamedTuple{(), Tuple{}}, fps::Int64)
   @ POMDPGifs ~/.julia/packages/POMDPGifs/AIFGJ/src/POMDPGifs.jl:145
 [7] simulate(s::GifSimulator, m::LaserTagPOMDP{DESPOTEmu, StaticArraysCore.MVector{8, Int64}}, p::POMDPTools.Policies.AlphaVectorPolicy{LaserTagPOMDP{DESPOTEmu, StaticArraysCore.MVector{8, Int64}}, Int64}, args::BasicParticleFilter{LaserTagPOMDP{DESPOTEmu, StaticArraysCore.MVector{8, Int64}}, LaserTagPOMDP{DESPOTEmu, StaticArraysCore.MVector{8, Int64}}, LowVarianceResampler, MersenneTwister, Vector{LTState}})
   @ POMDPGifs ~/.julia/packages/POMDPGifs/AIFGJ/src/POMDPGifs.jl:61
 [8] #makegif#4
   @ ~/.julia/packages/POMDPGifs/AIFGJ/src/POMDPGifs.jl:89 [inlined]
 [9] top-level scope
   @ show.jl:1047

The issue disappears after modifying line 64 in visualization.jl to use element-wise subtraction: .-

[zsunberg]

Thanks for reporting! Can you submit a PR to fix it?

[zlaouar]

Just submitted a pull request