CSCMatrix to dgMatrix not working with plain R command script

[tongjiyiming]

my script is
cat_train <- hashed.model.matrix( f, as.data.table(cat_train), HASHING_DIM_ )
I got

Error in as(retval, "dgCMatrix") : 
  no method or default for coercing “CSCMatrix” to “dgCMatrix”

when I run it in a command line terminal with plain R script environment. But, the code works inside Rstudio.

Please check

[wush978]

Please add:

library(methods)

at the beginning of your script and try again.