R:带有标记化和 %like% 的自创函数仅适用于第一个标记
R: Self-created function with tokenization and %like% works only on first token
我有一个两列的数据框,第二列(unit)主要包含第一列(str)的第一个单词。请查看以下内容:
> df <- data.frame(str = c("cups vegetable soup", "cup brown lentils", "carrot", "stalks celery"), unit = c("cups", "cup", NA, "stalks"), stringsAsFactors = FALSE)
> df
str unit
1 cups vegetable soup cups
2 cup brown lentils cup
3 carrot <NA>
4 stalks celery stalks
我想删除 $str 的第一个单词,如果它与 $unit 的对应值(在同一行)相匹配。
对于该范围,我创建了如下所示的函数 "DelFunction":
DelFunction <- function(x, y) {
tokens_x <- x[[1]]
tokens_y <- y[[1]]
if ((tokens_x %like% tokens_y) == TRUE) {
regmatches(tokens_x, regexpr("[a-z]+", tokens_x)) <- ""
}
tokens_x
}
在此之后,我在相应的行上使用了 sapply
df$str<- sapply(df$str, DelFunction, df$unit)
我得到以下结果,如您所见,代码仅适用于第一行,其中单词 "cups" 被删除。
> df
str unit
1 vegetable soup cups
2 cup brown lentils cup
3 carrot <NA>
4 stalks celery stalks
目标是获得以下结果
> df
str unit
1 vegetable soup cups
2 brown lentils cup
3 carrot <NA>
4 celery stalks
有人知道如何解决这个问题吗?
谢谢!
可能的答案:
library(stringr)
library(dplyr, warn.conflicts = FALSE)
df <-
data.frame(
str = c(
"cups vegetable soup",
"cup brown lentils",
"carrot",
"stalks celery"
),
unit = c("cups", "cup", NA, "stalks"),
stringsAsFactors = FALSE
)
df %>%
mutate(str = trimws(str_replace(str, unit, ''))) %>%
mutate(str = if_else(is.na(unit), df$str, str)) -> df2
df2
#> str unit
#> 1 vegetable soup cups
#> 2 brown lentils cup
#> 3 carrot <NA>
#> 4 celery stalks
无需(大量)更改原始代码的另一个可能答案:
library(DescTools)
df <-
data.frame(
str = c(
"cups vegetable soup",
"cup brown lentils",
"carrot",
"stalks celery"
),
unit = c("cups", "cup", NA, "stalks"),
stringsAsFactors = FALSE
)
DelFunction <- function(x, y) {
tokens_x <- x
tokens_y <- paste0(y, "%")
if ((tokens_x %like% tokens_y) == TRUE) {
regmatches(tokens_x, regexpr("[a-z]+", tokens_x)) <- ""
}
trimws(tokens_x)
}
df$str <- sapply(df$str, DelFunction, df$unit)
df
#> str unit
#> 1 vegetable soup cups
#> 2 brown lentils cup
#> 3 carrot <NA>
#> 4 celery stalks
我有一个两列的数据框,第二列(unit)主要包含第一列(str)的第一个单词。请查看以下内容:
> df <- data.frame(str = c("cups vegetable soup", "cup brown lentils", "carrot", "stalks celery"), unit = c("cups", "cup", NA, "stalks"), stringsAsFactors = FALSE)
> df
str unit
1 cups vegetable soup cups
2 cup brown lentils cup
3 carrot <NA>
4 stalks celery stalks
我想删除 $str 的第一个单词,如果它与 $unit 的对应值(在同一行)相匹配。
对于该范围,我创建了如下所示的函数 "DelFunction":
DelFunction <- function(x, y) {
tokens_x <- x[[1]]
tokens_y <- y[[1]]
if ((tokens_x %like% tokens_y) == TRUE) {
regmatches(tokens_x, regexpr("[a-z]+", tokens_x)) <- ""
}
tokens_x
}
在此之后,我在相应的行上使用了 sapply
df$str<- sapply(df$str, DelFunction, df$unit)
我得到以下结果,如您所见,代码仅适用于第一行,其中单词 "cups" 被删除。
> df
str unit
1 vegetable soup cups
2 cup brown lentils cup
3 carrot <NA>
4 stalks celery stalks
目标是获得以下结果
> df
str unit
1 vegetable soup cups
2 brown lentils cup
3 carrot <NA>
4 celery stalks
有人知道如何解决这个问题吗?
谢谢!
可能的答案:
library(stringr)
library(dplyr, warn.conflicts = FALSE)
df <-
data.frame(
str = c(
"cups vegetable soup",
"cup brown lentils",
"carrot",
"stalks celery"
),
unit = c("cups", "cup", NA, "stalks"),
stringsAsFactors = FALSE
)
df %>%
mutate(str = trimws(str_replace(str, unit, ''))) %>%
mutate(str = if_else(is.na(unit), df$str, str)) -> df2
df2
#> str unit
#> 1 vegetable soup cups
#> 2 brown lentils cup
#> 3 carrot <NA>
#> 4 celery stalks
无需(大量)更改原始代码的另一个可能答案:
library(DescTools)
df <-
data.frame(
str = c(
"cups vegetable soup",
"cup brown lentils",
"carrot",
"stalks celery"
),
unit = c("cups", "cup", NA, "stalks"),
stringsAsFactors = FALSE
)
DelFunction <- function(x, y) {
tokens_x <- x
tokens_y <- paste0(y, "%")
if ((tokens_x %like% tokens_y) == TRUE) {
regmatches(tokens_x, regexpr("[a-z]+", tokens_x)) <- ""
}
trimws(tokens_x)
}
df$str <- sapply(df$str, DelFunction, df$unit)
df
#> str unit
#> 1 vegetable soup cups
#> 2 brown lentils cup
#> 3 carrot <NA>
#> 4 celery stalks