R语言批量操作

By wangchangsheng | | 1 minutes
R Tidyverse

前言

在数据分析过程中，总是需要批量操作，如批量保存文件或批量作图。baseR的解法十分简单，for或while循环即可，但不够优雅。下面以tidyverse自带数据diamonds为例，以优雅的tidyverse流代码实现批量操作。

加载包和数据

library(tidyverse)
library(ggprism)
data("diamonds")

批量保存

diamonds %>%
  group_nest(cut) %>%
  pwalk(.l = list(.$cut, .$data),
        .f = ~ write.table(x = .y,
                           file = str_c(path, .x, ".txt"),
                           col.names = FALSE,
                           row.names = FALSE,
                           quote = FALSE))

批量作图

diamonds %>%
  group_nest(cut) %>%
  mutate(plot = map(data, ~ ggplot(data = .x) + 
                      geom_boxplot(aes(x = clarity, y = price, fill = clarity)) +
                      theme_prism() +
                      scale_fill_prism(palette = "winter_bright"))) %>%
  walk2(.x = .$cut,
        .y = .$plot,
        .f = ~ print(.y))

若想保存图片，将print替代为ggsave(filename = str_c(path, .x, “.pdf”), plot = .y)。