删除字符串 R 数据帧之后出现的行

Question

我想删除数据框列中某个字符串出现后的所有行。我只想 return A 列中出现在“总计”上方的 3 行。出现在“总计”下方的 2 行将被排除。

A            B       
Bob Smith    01005
Carl Jones   01008
Syndey Lewis 01185
total
Adam Price   01555
Megan Watson 02548

Answer 1

它有点笨拙，但这应该可以解决您想要它做的事情：

library(dplyr)

df <- data.frame(A = c("Bob Smith", "Carl Jones", "Sydney Lewis", "total", "Adam Price", "Megan Watson"),
                 B = c("01005", "01008", "01185", NA, "01555", "02548"))

index <- df[df$A=="total",] %>% rownames()
df %>% slice(1:index)

Answer 2

你可以使用

library(dplyr)

df %>% 
  filter(cumsum(A == "total") == 0)

这个returns

# A tibble: 3 x 2
  A            B    
  <chr>        <chr>
1 Bob Smith    01005
2 Carl Jones   01008
3 Syndey Lewis 01185

数据

structure(list(A = c("Bob Smith", "Carl Jones", "Syndey Lewis", 
"total", "Adam Price", "Megan Watson"), B = c("01005", "01008", 
"01185", NA, "01555", "02548")), problems = structure(list(row = 4L, 
    col = NA_character_, expected = "2 columns", actual = "1 columns", 
    file = "literal data"), row.names = c(NA, -1L), class = c("tbl_df", 
"tbl", "data.frame")), class = c("spec_tbl_df", "tbl_df", "tbl", 
"data.frame"), row.names = c(NA, -6L), spec = structure(list(
    cols = list(A = structure(list(), class = c("collector_character", 
    "collector")), B = structure(list(), class = c("collector_character", 
    "collector"))), default = structure(list(), class = c("collector_guess", 
    "collector")), skip = 1L), class = "col_spec"))

Answer 3

A <- c('Bob Smith','Carl Jones','Syndey Lewis','total','Adam Price','Megan Watson')

B <- c('01005','01008','01185','','01555','02548')

df <- data.frame(A, B) 

val =  which(df$A=="total")  #get index of total

C = df[1:val-1,]

Answer 4

我们可以用 row_number 和 which

进行子集化

library(dplyr)

df %>% filter(row_number() < which(A=='total'))

             A     B
1    Bob Smith 01005
2   Carl Jones 01008
3 Syndey Lewis 01185

删除字符串 R 数据帧之后出现的行

Remove Rows occurring after a String R Data frame

r

data-manipulation

dplyr

数据