map_pmap_example.R

library(tidyverse)

#-----------------------------------------------------------------------------
# Some complicated function to calculate things.
#-----------------------------------------------------------------------------
complex_func <- function(df) {
  cat("processing: ", first(df[['ID']]), "\n")

  # 100 lines of code go here.

  df %>% mutate(something_complex_to_calculate = row_number())
}

#-----------------------------------------------------------------------------
# Project One - ID labels are unique across entire project
#-----------------------------------------------------------------------------
project_one <- readr::read_csv(
'ID, value1, value2
1  ,      1,      1
1  ,      1,      2
2  ,      2,      1
2  ,      2,      2
3  ,      3,      1
3  ,      3,      2
')


#-----------------------------------------------------------------------------
# Project 1 processing
#-----------------------------------------------------------------------------
project_one %>%
  group_by(ID) %>%
  do(complex_func(.)) %>%
  ungroup()


#-----------------------------------------------------------------------------
# Some complicated function to calculate things.
#-----------------------------------------------------------------------------
complex_func2 <- function(df, ID) {
  cat("processing: ID =", ID, "\n")

  # 100 lines of code go here.

  df %>% mutate(something_complex_to_calculate = row_number())
}



project_one %>%
	nest(-ID) %>%
	mutate(data = map2(data, ID, ~ complex_func2(.x, .y))) %>%
	unnest()


#-----------------------------------------------------------------------------
# Project Two.  ID labels are only unique within GROUP
#-----------------------------------------------------------------------------
project_two <- readr::read_csv(
'ID, GROUP, value1, value2
1  ,     1,      1,      1
1  ,     1,      1,      2
2  ,     1,      2,      1
2  ,     1,      2,      2
1  ,     2,      3,      1
1  ,     2,      3,      2
')


#-----------------------------------------------------------------------------
# Project Two - processing.
#-----------------------------------------------------------------------------
project_two %>%
  group_by(GROUP, ID) %>%
  do(complex_func(.)) %>%
  ungroup()


#-----------------------------------------------------------------------------
# Some complicated function to calculate things.
#-----------------------------------------------------------------------------
complex_func3 <- function(df, ID, GROUP) {
  cat("processing: ID = ", ID, "GROUP = ", GROUP , "\n")

  # 100 lines of code go here.

  df %>% mutate(something_complex_to_calculate = row_number())
}

project_two %>%
	nest(-ID, -GROUP) %>%
	mutate(data = pmap(.l = list(data, ID, GROUP), .f = ~complex_func3(..1, ..2, ..3))) %>%
	unnest()