declare output format for data matrix

[topepo]

Until there is a sparse tibble (I hope one day), there should be an option for process to convert the output to a sparse matrix format such as Matrix::dgCMatrix. See vignette("Intro2Matrix")

[topepo]

A better option would be for bake and juice to have a format argument that defaults to "tibble" but could be "matrix", "dgCMatrix", or others.

[topepo]

A check for all of the same data type would need to occur for matrix and spare matrix formats. The summary method along with the selectors should make this easy.

[jeffwong-nflx]

Being able to output a sparse matrix would be hugely valueable! My research uses a lot of categorical variables, so I can benefit a lot from sparse matrices. Thanks!

[topepo]

@jeffwong-nflx Take a look at this and see if it fits your needs.

[jeffwong-nflx]

Thanks Max, I will take a look

[samyishak]

This feature is fantastic! Is there a way to specify that a recipe object outputs a sparse matrix when using caret:::train.recipe?

[topepo]

Unfortunately, no. I'm loath to add another argument to trainControl.