从数据框中删除所有引号

Question

我有一个如下所示的数据框rep:

> head(rep)
     position chrom  value label  
[1,] "17408"  "chr1" "0"   "miRNA"
[2,] "17409"  "chr1" "0"   "miRNA"
[3,] "17410"  "chr1" "0"   "miRNA"
[4,] "17411"  "chr1" "0"   "miRNA"
[5,] "17412"  "chr1" "0"   "miRNA"
[6,] "17413"  "chr1" "0"   "miRNA"

如何从所有元素中删除引号？

注意:rep$position并且rep$value应该是numerictype,rep$chrom并且rep$label应该是charactertype.

Answer 1

两步:1)去掉引号,2)相应地转换列:

数据

x <- read.table(text='
position chrom  value label  
"\\"17408\\""  "\\"chr1\\"" "\\"0\\""   "\\"miRNA\\""
"\\"17409\\""  "\\"chr1\\"" "\\"0\\""   "\\"miRNA\\""'
, header=T)

1)摆脱引号

library(stringr)
library(plyr)

del <- colwise(function(x) str_replace_all(x, '\"', ""))
x <- del(x)

2)相应地转换列

num <- colwise(as.numeric)    
x[c(1,3)] <- num(x[c(1,3)])
x

  position chrom value label
1    17408  chr1     0 miRNA
2    17409  chr1     0 miRNA

Answer 2

如@Roland所示,你有一个matrix,而不是一个data.frame,它们有不同的默认print方法.坚持使用matrix,您可以quote = FALSE明确设置print或使用noquote.

这是一个基本的例子:

## Sample data
x <- matrix(c(17, "chr1", 0, "miRNA", 18, "chr1", 0, "miRNA"), nrow = 2, 
            byrow = TRUE, dimnames = list(
              NULL, c("position", "chrom", "value", "label")))

## Default printing
x
#      position chrom  value label  
# [1,] "17"     "chr1" "0"   "miRNA"
# [2,] "18"     "chr1" "0"   "miRNA"

## Two options to make the quotes disappear
print(x, quote = FALSE)
#      position chrom value label
# [1,] 17       chr1  0     miRNA
# [2,] 18       chr1  0     miRNA
noquote(x)
#      position chrom value label
# [1,] 17       chr1  0     miRNA
# [2,] 18       chr1  0     miRNA

此外,正如您自己想出的那样,将您转换matrix为a data.frame会使引号消失.data.frame如果每列是不同类型的数据(数字,字符,因子等),则A 是更合适的结构来保存数据.但是,将a转换matrix为a data.frame不会自动为您转换列.相反,您可以使用type.convert(在创建data.frame使用read.table和族时也使用):

y <- data.frame(x, stringsAsFactors = FALSE)
str(y)
# 'data.frame':  2 obs. of  4 variables:
#  $ position: chr  "17" "18"
#  $ chrom   : chr  "chr1" "chr1"
#  $ value   : chr  "0" "0"
#  $ label   : chr  "miRNA" "miRNA"
y[] <- lapply(y, type.convert)
str(y)
# 'data.frame':  2 obs. of  4 variables:
#  $ position: int  17 18
#  $ chrom   : Factor w/ 1 level "chr1": 1 1
#  $ value   : int  0 0
#  $ label   : Factor w/ 1 level "miRNA": 1 1
y
#   position chrom value label
# 1       17  chr1     0 miRNA
# 2       18  chr1     0 miRNA