问题描述
我在两天内测量了两种土壤类型的化合物排放量。
现在我想计算每天每种土壤类型的总排放量中有多少丙酮和乙醛。我想在我的数据中创建一个新列，例如（丙酮排放量/总排放量）*100 计算。
有什么想法吗？
这是数据
df <- structure(list(soil_type = c("SOC<10","SOC<10","SOC>10","SOC>10"),compound = c("Acetaldehyde","Acetaldehyde","Acetone","Total emission","Total emission"),day = c(0L,4L,0L,4L),mean = c(0.03,0.07,0.02,0.04,0.06,0.11,0.01,0.05,0.08,0.13)),row.names = c(NA,-12L),groups = structure(list(soil_type = c("SOC<10","Total emission"
),.rows = structure(list(1:2,3:4,5:6,7:8,9:10,11:12),ptype = integer(0),class = c("vctrs_list_of","vctrs_vctr","list"))),-6L),class = c("tbl_df","tbl","data.frame"),.drop = TRUE),class = c("grouped_df","tbl_df","data.frame"))
解决方法
对于每个 soil_type 和 day，您可以计算丙酮排放量/总排放量*100 的比率。
library(dplyr)
df %>%
group_by(soil_type,day) %>%
mutate(ratio = mean[match('Acetone',compound)]/
mean[match('Total emission',compound)] * 100) %>%
ungroup -> result
result
# soil_type compound day mean ratio
# <chr> <chr> <int> <dbl> <dbl>
# 1 SOC<10 Acetaldehyde 0 0.03 33.3
# 2 SOC<10 Acetaldehyde 4 0.07 36.4
# 3 SOC<10 Acetone 0 0.02 33.3
# 4 SOC<10 Acetone 4 0.04 36.4
# 5 SOC<10 Total emission 0 0.06 33.3
# 6 SOC<10 Total emission 4 0.11 36.4
# 7 SOC>10 Acetaldehyde 0 0.01 62.5
# 8 SOC>10 Acetaldehyde 4 0.04 53.8
# 9 SOC>10 Acetone 0 0.05 62.5
#10 SOC>10 Acetone 4 0.07 53.8
#11 SOC>10 Total emission 0 0.08 62.5
#12 SOC>10 Total emission 4 0.13 53.8