Shuffle (jl)

using Plots

function NaiveShuffle(x)
    r=copy(x)
    l=length(r)
    for i in 1:l
        j=rand(1:l)
        r[[i,j]]=r[[j,i]]
    end
    r
end

function FisherShuffle(x)
    r=copy(x)
    l=length(r)
    for i in 1:l
        j=rand(i:l)
        r[[i,j]]=r[[j,i]]
    end
    r
end

function SampleShuffle(n,tr=1000000)
    RN=Dict()
    RF=Dict()
    for _ in 1:tr
        r=collect(1:n)
        s0=NaiveShuffle(r)
        s1=FisherShuffle(r)
        (s0∈keys(RN)) ? (RN[s0]+=1) : RN[s0]=1
        (s1∈keys(RF)) ? (RF[s1]+=1) : RF[s1]=1
    end
    Dict([ k=>[RN[k] RF[k]]./tr for k in keys(RN)∩keys(RF) ])
end

function plotShuffle(n,tr=1000000)
    R=SampleShuffle(n,tr)
    vals=reduce(vcat,values(R))
    scatter(vals,label=["Naive" "Fisher"],xrotation=30,xticks=(1:1:length(vals),collect(keys(R))))
end


X=plotShuffle(4)