Question

我有这样的数据集：

Name|Material |Project  
John|LS       |222  
Jack|Limestone|111  
Job |LI       |121

我想用材质栏中的Limestone替换LS和LI 我试过这个LS：

ds$Material[ds$material %in% grep("^LS^",ds$Material,ignore.case = TRUE)]<-"Limestone"

但该栏目中还有一堆LS。有什么想法吗？

Answer 1

您还可以使用gsub()将LI和LS替换为Limestone：

ds$Material <- gsub("LS|LI", "Limestone", ds$Material)
#   Name Materials Project
# 1 John Limestone     222
# 2 Jack Limestone     111
# 3  Job Limestone     121

Answer 2

您的数据框

f1

ds <- 
    read.table(text = "Name Material Project
                        John LS        222  
                        Jack Limestone 111  
                        Job  LI        121  
                      ", header = TRUE, stringsAsFactors = FALSE)

对仅找到> ds Name Material Project 1 John LS 222 2 Jack Limestone 111 3 Job LI 121的列进行子集。

LS

结果

ds$Material[grep("^L[SI]$", ds$Material, ignore.case = TRUE)] <- "Limestone"

在dplyr：

> ds
  Name  Material Project
1 John Limestone     222
2 Jack Limestone     111
3  Job        LI     121

Answer 3

使用dplyr：

df <- tibble(Name = c("John", "Jack", "Job"), Material = c("LS", "Limestone", "LI"), Project = c(222, 111, 121))

df %>% mutate(Material = stringr::str_trim(Material)) %>%  
        mutate(Material = case_when(
                              Material %in% c('LS', 'LI') ~ 'Limestone',
                              TRUE ~ Material
                              )
              )

Answer 4

使用基础R，您可以使用ifelse。

# Reproducible example
data <- read.table(textConnection("Name|Material |Project  
                                   John|LS       |222  
                                   Jack|Limestone|111  
                                   Job |LI       |121  "),
                   sep = "|", row.names = NULL, header = TRUE,
                   stringsAsFactors = FALSE, strip.white = TRUE)
data$Material <- ifelse(data$Material %in% c("LS", "LI"), "Limestone", data$Material)

替换R中相同列和相同数据集中的值

4 个答案: