如何使用过滤器函数进行for循环？

Question

I'm having a problem with using the filter() function inside a for loop , it doesn't filter the data frame and instead creates an i value. The code is below:

    library(tidyverse)
    library(magrittr)
    library(dplyr)
    funcexrds <- readRDS("C:/Users/chlav/Dropbox/Antidumping/Data/ano_pais_imp/funcex.rds")
    funcexrds <- funcexrds %>% arrange(desc_cnae, pais)
    View(funcexrds)
    funcexpais_lista <- funcexrds %>% select(pais) %>% as.list()
    funcexcnae_lista <- funcexrds %>% select(desc_cnae) %>% as.list()
    subset1 <- filter(funcexrds, pais == "África do Sul", desc_cnae == "Abate de reses, exceto suínos")
    for (i in 1:length(unique(funcexpais_lista))) {
        funcexrds_t <- filter(funcexrds, pais == "i") 
    }

As you can see if you reproduce the code, subset1 returns the filtered dataset as you expect, but the for loop doesn't

Answer 1

I agree with @Clemsang. If you're trying to get the for loop to pull out whatever relevant information is at Pais == 1, Pais == 2, etc. putting i outside of quotes effectively shows the for loop where to put the number you indicated in

for (i in 1:length(unique(funcexpais_lista)))

Also just some housekeeping to keep in mind, since tidyverse already contains the dplyr and magrittr functions, you should only need to load tidyverse before starting your code!