Julia 中的并行雅可比

Question

我正在尝试并行运行这个 Jacobi 代码，但它不起作用：

using Distributed
addprocs(2)
@everywhere using LinearAlgebra
@everywhere using DistributedArrays

@everywhere  n=5
@everywhere  m=n^2
I=Diagonal(ones(n,n))
A = Tridiagonal([fill(-1, n-2); -1], fill(2, n), [-1; fill(-1, n-2);])
A=kron(A,I)+kron(I,A)
b=ones(m,1)
x=ones(m,1)
d=ones(m,1)

A=distribute(A; dist=(2,1))
b=distribute(b; dist=(2,1))
x=distribute(x; dist=(2,1))
d=distribute(d; dist=(2,1))
D = distribute(ones(size(A,1),1); dist=(nworkers(), 1))  
@everywhere Δx=[]

@sync @distributed for z in 1:2
    for i in 1:8
        D_local=localpart(D)
        x_local=localpart(x)
        A_local=localpart(A)
        b_local=localpart(b)
            for j in 1:16
                if i!== j
                    global xx
                    x_local = x_local + inv(D_local)[i,i].*(b_local - A_local*x_local)
                end
            end
    end
    return xx
end

Answer 1

没关系我知道了already.thank你

using Distributed
addprocs(2)
@everywhere using LinearAlgebra
@everywhere using DistributedArrays

@everywhere  n=6
@everywhere  m=n^2
I=Diagonal(ones(n,n))
A = Tridiagonal([fill(-1, n-2); -1], fill(2, n), [-1; fill(-1, n-2);])
A=kron(A,I)+kron(I,A)
b=ones(m,1)
x=ones(m,1)
d=ones(m,1)

A=distribute(A; dist=(2,1))
b=distribute(b; dist=(2,1))
x=distribute(x; dist=(2,1))
d=distribute(d; dist=(2,1))
D = distribute(4*ones(size(A,1),1); dist=(2, 1))
maxit = 100
for z in 1:maxit
    @sync @distributed for t in 1:2
        for i in 1:length(localindices(A)[1])
            localpart(x)[i] =  localpart(x)[i] + ( localpart(b)[i] -  localpart(A*x)[i])./localpart(D)[i]
        end
        println(x)
    end
end

using Plots
plot(convert(Array,x))

x

Julia 中的并行雅可比

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