Columns to dummies in R, example provided [duplicate]

Answer 1

Usually better way for such dummy coding is to use sparse matrices and Matrix::sparse.model.matrix :

Matrix::sparse.model.matrix(uid ~ -1 + ., data=your_data_frame)

Answer 2

Try with reshape2. Like here:

library("reshape2")

dcast(cbind(z, ile=1), 
      uid~language_name, value.var="ile", fill=0) -> t

colnames(t)[-1] <- paste("Language_", colnames(t)[-1], sep="")