Print data frame dimensions at each step of filtering

Question

I am using the tidyverse to filter out a dataframe and would like a print at each step of the dimensions (or nrows) of the intermediate objects. I thought I could simply use

Answer 1

@akrun's idea works, but it's not idiomatic tidyverse. Other functions in the tidyverse, like print() and glimpse() return the data parameter invisibly so they can be piped without resorting to {}. Those {} make it difficult to clean up pipes after your done exploring what's going on.

Try:

library(tidyverse)

tidydim <- function(x) {
  print(dim(x))
  invisible(x)
}

mtcars %>%
  filter(cyl > 4) %>%
  tidydim() %>% 
  filter(., am == 0) %>%
  tidydim() %>% 
  filter(., disp >= 200) %>%
  tidydim()

That way your "cleanup" (i.e. not producing interim console output) canbe to quickly/easily remove the tidydim() lines or remove the print(…) from the function.