请教下面这个code 有什么问题,为什么运行不了?多谢
nmj<-matrix(5,50,20)
Mnmj<-matrix(1,50,20)
for (t in 1:49){
Mnmj[t,c(1:10)]=0.9*nmj[t, c(1:10)]
Mnmj[t,c(11:20)]=1.2*nmj[t, c(11:20)]
j=1
for (j in 1:20){
if(j==1){
nmj[t+1,j]=(1-0.1)*Mnmj[t,j]+0.1*Mnmj[t,j+1]
} else {
if (j>=2 | j<=19){
nmj[t+1,j]=(1-2*0.1)*Mnmj[t,j]+0.1*Mnmj[t,j-1]+0.1*Mnmj[t,j+1]
} else {if (j==20){
nmj[t+1,j]=(1-0.1)*Mnmj[t,j]+0.1*Mnmj[t,j-1]
}
j=j+1
}}}}
nmj