R 如何在两个特定值之间筛选行

我需要帮助过滤以下数据帧（这是一个简单的示例）：

我需要根据第二列（距离）进行过滤，使其如下所示：

  mutation distance
3        -    FALSE
4        -    FALSE
5 mutation    FALSE
6        +    FALSE

---

我需要删除所有行，直到最后一行

TRUE

，该行位于具有

mx$mutation=mutation

值的行之前（因此第1行和第2行），以及在

mx$mutation=mutation

之后发生的第一行

TRUE

之后的所有行（因此第7行和以后）

library(dplyr)
mx %>%
  group_by(grp = cumsum(distance)) %>% 
  filter(any(mutation == "mutation") & !distance) %>%
  ungroup %>% 
  select(-grp)
# A tibble: 4 x 2
# mutation distance
#  <fctr>   <lgl>   
#1 -        F       
#2 -        F       
#3 mutation F       
#4 +        F       

希望这有帮助

#示例数据（注意，我在末尾添加了一些额外的行）
mx=data.frame（突变=c（“-”、“-”、“-”、“-”、“-”、“突变”、“+”、“+”、“+”、“+”、“-”、“突变”、“+”、“+”），
距离=c（F，T，F，F，F，F，F，T，F，F，F，F，T））
突变\u idx您可以使用which（）方法适当地标识行：

# get rownum of last TRUE before df$mutation=mutation
last_true_before_mutation <- max(which(mx$distance == 'TRUE')[which(mx$distance == 'TRUE') < which(mx$mutation == 'mutation')])

# get rownum of first TRUE after df$mutation=mutation
first_true_after_mutation <- min(which(mx$distance == 'TRUE')[which(mx$distance == 'TRUE') > which(mx$mutation == 'mutation')])

# all rows to remove 
rem_rows <- c(seq(1:last_true_before_mutation), seq(first_true_after_mutation, nrow(mx)))

# remove approproate rows
mx[-rem_rows, ]


mx = data.frame(c("-", "-", "-", "-", "mutation", "+", "+", "+", "+") ,
                      c(F, T, F, F, F, F, T, F,T)) 

   mutation distance
3         -    FALSE
4         -    FALSE
5  mutation    FALSE
6         +    FALSE
10        -    FALSE
11 mutation    FALSE
12        +    FALSE

# get rownum of last TRUE before df$mutation=mutation
last_true_before_mutation <- max(which(mx$distance == 'TRUE')[which(mx$distance == 'TRUE') < which(mx$mutation == 'mutation')])

# get rownum of first TRUE after df$mutation=mutation
first_true_after_mutation <- min(which(mx$distance == 'TRUE')[which(mx$distance == 'TRUE') > which(mx$mutation == 'mutation')])

# all rows to remove 
rem_rows <- c(seq(1:last_true_before_mutation), seq(first_true_after_mutation, nrow(mx)))

# remove approproate rows
mx[-rem_rows, ]

before_after_mutation <- function(df) {
    last_true_before_mutation <- max(which(df$distance == 'TRUE')[which(df$distance == 'TRUE') < which(df$mutation == 'mutation')])
    first_true_after_mutation <- min(which(df$distance == 'TRUE')[which(df$distance == 'TRUE') > which(df$mutation == 'mutation')])
    rem_rows <- c(seq(1:last_true_before_mutation), seq(first_true_after_mutation, nrow(df)))
    res <- df[-rem_rows,]
    return(res)
}

before_after_mutation(mx)