Thank you for your great R package "mlr". I am interested in calculate survival probability for my RNA-seq data. I want to use surv. function in "mlr" package for this. I applied surv.glmboost, surv.gamboost, surv.cforest, surv.ranger etc. for calculating c-index and I did not encounter a problem. However, I get an error when I use surv.glmnet or surv.cvglmnet function. The error is below:

"Error in (function (x, y, family = c("gaussian", "binomial", "poisson", :
x should be a matrix with 2 or more columns"

So, how should I define "matrix X" ?

I try to use mlr3 and mlr3proba for survival analysis, but I don't apply feature selection methods.