问题描述
我想将 df1
中的值除以 df2
中的值。在这个可重现的示例中,我能够对这些值求和。分工呢?提前致谢!
df1 <- data.frame(country = c("a","b","c"),year1 = c(1,2,3),year2 = c(1,3))
df2 <- data.frame(country = c("a","d"),NA),3))
df3 <- bind_rows(df1,df2) %>%
mutate_if(is.numeric,tidyr::replace_na,0) %>%
group_by(country) %>%
summarise_all(.,sum,na.rm = TRUE) %>%
na_if(.,0)
预期结果是:
# A tibble: 4 x 3
country year1 year2
<chr> <dbl> <dbl>
1 a 1 1
2 b 1 1
3 c NA NA
4 d NA NA
解决方法
由于有 2 行的组和 1 行的组,请在 if/else
中使用 summarise/across
条件将 first
元素除以 last
if
有两个元素或 else
return NA
library(dplyr) # version 1.0.4
library(tidyr)
bind_rows(df1,df2) %>%
mutate(across(where(is.numeric),replace_na,0)) %>%
group_by(country) %>%
summarise(across(everything(),~ if(n() == 2) first(.)/last(.)
else NA_real_))
-输出
# A tibble: 4 x 3
# country year1 year2
#* <chr> <dbl> <dbl>
#1 a 1 1
#2 b 1 1
#3 c NA NA
#4 d NA NA
,
这是使用 merge
+ split.default
df <- merge(df1,df2,by = "country",all = TRUE)
cbind(
df[1],list2DF(lapply(
split.default(df[-1],gsub("\\.(x|y)","",names(df)[-1])),function(v) do.call("/",v)
))
)
给出
country year1 year2
1 a 1 1
2 b 1 1
3 c NA NA
4 d NA NA