r - RSNNS elman network Predict -

i new user of r , neural networks, read rsnns tutorial, not find how predict sequane of series until end. exemple :

require ( rsnns ) mydata <- read.csv("mydata.csv",header = true) mydata.train <- mydata[1:1000,] mydata.test <- mydata[1001:1500,]  set.seed(0) fit <- elman ( mydata.train[1001:1500,], mydata.train[,1], size=100,                 learnfuncparams=c(0.1) , maxit=1000 )  pred <- predict ( fit , mydata.test[1001:1500,] ) 

but, size of pred equal size of test,how can do, predict obtain serie until end of mydata.train.

thank you.