dplyr链中的write.csv()

Question

我之前遇到过这个问题,但只是在链外写了导出函数.有没有办法write.csv在dplyr链中包含一个语句？

library(dplyr)

data_set %>%
filter(Date == Sys.Date() - 1 | Date == Sys.Date()) %>%
write.csv('data_set_twodays.csv', row.names = F) %>%
filter(Date = Sys.Date()) %>%
write.csv('data_set_today.csv', row.names = F)
NULL

Answer 1

这在0.2版本中似乎对我有用:

mtcars %>% filter(cyl == 4) %>% write.csv(.,file = "~/Desktop/piping.csv")

Answer 2

你正在寻找T管道:

%T>% 将运行该函数,但将输入作为输出传递

library(dplyr)
library(magrittr)

data_set %>%
filter(Date == Sys.Date() - 1 | Date == Sys.Date()) %T>%
write.csv('data_set_twodays.csv', row.names = F) %>%
filter(Date = Sys.Date()) %T>%
write.csv('data_set_today.csv', row.names = F) 

人们经常使用它来绘制中间体而不会破坏管道!

来自文档:

rnorm(200) %>%
matrix(ncol = 2) %T>%
plot %>% # plot usually does not return anything. 
colSums