data <- readLines(con = textConnection("014003051906,ETN5080 ,0450,BOLT KIT UPPER SHAFT WITH 5 SPEED,1.000,F
014003051906,ETN5967 ,0460,SENSOR SENSOR FH BACKSHAFT SPEED,1.000,F
014003051906,ETN64267 ,0470,TILT UNIT SENSOR,1.000,F
014003065376,03M7184 ,0020,BOLT - M 8.0 X 1.250 X 20.0 - 8.8-Zinc,4.000,G
014003065376,03M7386 ,0090,BOLT, RD HD SQ SHORT NECK, METRIC,18.000,G
014003065376,14M7296 ,0090,NUT, METRIC, HEX FLANGE,14.000,G"))
pattern <- "^([^,]*),([^,]*),([^,]*),(.*),([^,]*),([^,]*)$"
library(stringr)
str_match(data, pattern)[, - 1]
# [,1] [,2] [,3] [,4] [,5] [,6]
# [1,] "014003051906" "ETN5080 " "0450" "BOLT KIT UPPER SHAFT WITH 5 SPEED" "1.000" "F"
# [2,] "014003051906" "ETN5967 " "0460" "SENSOR SENSOR FH BACKSHAFT SPEED" "1.000" "F"
# [3,] "014003051906" "ETN64267 " "0470" "TILT UNIT SENSOR" "1.000" "F"
# [4,] NA NA NA NA NA NA
# [5,] "014003065376" "03M7184 " "0020" "BOLT - M 8.0 X 1.250 X 20.0 - 8.8-Zinc" "4.000" "G"
# [6,] "014003065376" "03M7386 " "0090" "BOLT, RD HD SQ SHORT NECK, METRIC" "18.000" "G"
# [7,] "014003065376" "14M7296 " "0090" "NUT, METRIC, HEX FLANGE" "14.000" "G"
Edit:
为初学者提供的正则表达式解释,简单易懂,因此请原谅不准确之处:
- Initial
^
和终端$
表示字符串的开始和结束。
- 括号用于分组(组
str_match()
将提取)。
-
.
表示任何字符,并且.*
表示任意数量的任意字符。
-
[^,]
表示不是逗号的任何字符。
当放在一起时,这意味着:start of string
- substring without a comma
- comma
(重复3次)-substring possibly containing commas
- comma
- substring without a comma
- comma
- substring without a comma
- end of string
,并且仅提取括号内的组。