R中的文本挖掘-从以关键字开头的文本文件中删除行

Question

我正在将一个文本文件读入 R，如下所示：

test<-readLines("D:/AAPL MSFT Earnings Calls/Test/Test.txt")

此文件是从 PDF 转换而来的，并保留了一些我想删除的标题数据。它们将以“页面”、“市值”等词开头。

如何删除 TXT 文件中以这些关键字开头的所有行？这与删除包含该单词的行相反。

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使用下面的答案之一，我修改了一下以阅读

setwd("C:/Users/George/Google Drive/PhD/Strategic agility/Source Data/Peripherals Earnings Calls 2016")
text1<-readLines("test.txt")
text

library(purrr)
library(stringr)
text1 <- "foo
Page, bar
baz
Market Cap, qux"
text1 <- readLines(con = textConnection(file))
ignore_patterns <- c("^Page,", "^Market\\s+Cap,")
text1 %>% discard(~ any(str_detect(.x, ignore_patterns)))

text1

这是我得到的输出：

> text1
[1] "foo"             "Page, bar"       "baz"             "Market Cap, qux"

什么是 foo/baz/qux 字符？谢谢你

Answer 1

# once you have read and stored in a data.frame
# perform below subsetting :
x = grepl("^(Page|Market Cap)", df$id) # where df is you data.frame and 'id' is your 
                                       # column name that has those unwanted keywords
df <- df[!x,]  # does the job!

^ 帮助检查开始。因此，如果行以Page 或(|)Market Cap 开头，则grepl 返回TRUE

Answer 2

library(purrr)
library(stringr)
file <- "foo
Page, bar
baz
Market Cap, qux"
test <- readLines(con = textConnection(file))
ignore_patterns <- c("^Page,", "^Market\\s+Cap,")
test %>% discard(~ any(str_detect(.x, ignore_patterns)))