如何用R中的NA替换特定行和列中的某些值?
在我的数据框中,我想用NA替换某些空白单元格和值单元格。但我想用NAs替换的单元格与单元格存储的值无关,而是与它存储的行和列的组合有关 下面是一个示例数据帧DF:如何用R中的NA替换特定行和列中的某些值?,r,dplyr,R,Dplyr,在我的数据框中,我想用NA替换某些空白单元格和值单元格。但我想用NAs替换的单元格与单元格存储的值无关,而是与它存储的行和列的组合有关 下面是一个示例数据帧DF: Fruits Price Weight Number of pieces Apples 20 2 10 Oranges 15 4 16 Pineapple 40 8 6 Avocado
Fruits Price Weight Number of pieces
Apples 20 2 10
Oranges 15 4 16
Pineapple 40 8 6
Avocado 60 5 20
我想把菠萝的重量换成NA,把橙子的件数换成NA
DF$Weight[3] <- NA
DF$`Number of pieces`[2] <- NA
但若表格的顺序改变,这将用NA替换错误的值
我应该怎么做呢?因为数据结构是二维的,所以可以先找到包含特定值的行的索引,然后使用这些信息
which(DF$Fruits == "Pineapple")
[1] 3
DF$Weight[which(DF$Fruits == "Pineapple")] <- NA
which(DF$Fruits==“菠萝”)
[1] 3
DF$重量[其中(DF$水果==“菠萝”)]
结果:由于读取数据,碎片数被截断为数字
Fruits Price Weight Number
1 Apples 20 2 10
2 Oranges 15 4 NA
3 Pineapple 40 NA 6
4 Avocado 60 5 20
下面是一种使用函数is.n的方法。您打算替换多少行?我的数据集中有37行26列。我打算用NA替换不同行/列组合中的至少10个单元格。
library(dplyr)
df %>%
mutate(Weight=ifelse(Fruits=="Pineapple",NA,Weight),
Number=ifelse(Fruits=="Oranges",NA,Number))#use Number of Pieces
Fruits Price Weight Number
1 Apples 20 2 10
2 Oranges 15 4 NA
3 Pineapple 40 NA 6
4 Avocado 60 5 20
is.na(DF$Weight) <- DF$Fruits == "Pineapple"
is.na(DF$`Number of pieces`) <- DF$Fruits == "Oranges"
DF
# Fruits Price Weight Number of pieces
#1 Apples 20 2 10
#2 Oranges 15 4 NA
#3 Pineapple 40 NA 6
#4 Avocado 60 5 20
DF <-
structure(list(Fruits = structure(c(1L, 3L, 4L, 2L),
.Label = c("Apples", "Avocado", "Oranges", "Pineapple"),
class = "factor"), Price = c(20L, 15L, 40L, 60L),
Weight = c(2L, 4L, 8L, 5L), `Number of pieces` = c(10L,
16L, 6L, 20L)), class = "data.frame", row.names = c(NA, -4L))