用R语言做神经网络聚类的时候，绘制图像出现错误，求帮忙解决，程序附在下方
library(kohonen)

set.seed(12345)
Data=matrix(rnorm(n=100,mean=0,sd=1),ncol=2,byrow=TRUE)
Data[1:25,1]=Data[1:25,1]+3
Data[1:25,2]=Data[1:25,2]-4
set.seed(12345)
Data=as.matrix(Data)
My.som=som(Data,grid=somgrid(xdim=1,ydim=2,topo="rectangular"))
My.som
summary(My.som)
plot(My.som

$

data,pch=

My.som$unit.classif

,main="模拟数据SOM网络聚类结果",xlab="x1",ylab="x2")
Error in xy.coords(x, y, xlabel, ylabel, log) :
  'x' is a list, but does not have components 'x' and 'y'