exporting and saving a list of ggplots objects with names based on a column-CodePudding

been an R user for around a year now - so still have tons to learn. Anyways my question is:

How do I export the ggplots within the list and name them specifically based on their location.

Below is the dummy data I have created with where I am at.

location <- c('obs1', 'obs2', 'obs3', 'obs4', 'obs5', 'obs6')
percentage <- c(40, 30, 20, 40, 20, 30)
mean_percentage <- c(30, 30, 30, 30, 30, 30)

dat1 <- data.frame(location, percentage, mean_percentage)

plot.func <- function(dat) {
  
  dat %>% 
    pivot_longer(cols = 2:3, names_to = 'place', values_to = 'percent') %>%
    ggplot(aes(x = place, y = percent, fill = place))  
    geom_bar(stat = 'identity')
  
}

myplots <- list()

myplots <- lapply(1:nrow(dat1), function(i) plot.func(dat1[i,]))

The above code produces the list called 'myplots' which contains 6 ggplots.

I would like to export these individually with names based on the location variable.

For example: obs1.barchart.pdf, obs2.barchart.pdf, obs3.barchart.pdf and so on.

I've tried various different ways but going round in circles. Any help much appreciated.

Best, TheBoomerang

CodePudding user response：

One option would be to name your lists of plots and use purrr::imap or purrr::iwalk to loop over the list of plots to save them.

For convenience I use split to first split you data by location which will create a named list of dataframe on which I apply your function using lapply before passing it to iwalk to save the plots using ggsave:

library(ggplot2)
library(dplyr)
library(tidyr)

split(dat1, dat1$location) |> 
  lapply(plot.func) |> 
  purrr::iwalk(~ ggsave(paste(.y, "barchart", "pdf", sep = "."), plot = .x))
#> Saving 7 x 5 in image
#> Saving 7 x 5 in image
#> Saving 7 x 5 in image
#> Saving 7 x 5 in image
#> Saving 7 x 5 in image
#> Saving 7 x 5 in image