如何使用R或PowerShell从文本文件中提取数据?

时间:2012-01-24 13:23:23

标签: r powershell powershell-v2.0 text-processing

我有一个包含以下数据的文本文件:

This is just text
-------------------------------
Username:          SOMETHI           C:                 [Text]
Account:           DFAG              Finish time:        1-JAN-2011 00:31:58.91
Process ID:        2028aaB           Start time:        31-DEC-2010 20:27:15.30

This is just text
-------------------------------
Username:          SOMEGG            C:                 [Text]
Account:           DFAG              Finish time:        1-JAN-2011 00:31:58.91
Process ID:        20dd33DB          Start time:        12-DEC-2010 20:27:15.30

This is just text
-------------------------------
Username:          SOMEYY            C:                 [Text]
Account:           DFAG              Finish time:        1-JAN-2011 00:31:58.91
Process ID:        202223DB          Start time:        15-DEC-2010 20:27:15.30

有没有办法从这种数据中提取用户名,完成时间,开始时间?我正在寻找一些起点使用R或Powershell。

4 个答案:

答案 0 :(得分:8)

R可能不是处理文本文件的最佳工具,但您可以按以下步骤操作:通过将文件作为固定宽度文件读取来识别两列,通过在冒号上分割字符串将字段与其值分开,添加一个“id”列,并将所有内容整理回来。

# Read the file
d <- read.fwf("A.txt", c(37,100), stringsAsFactors=FALSE)

# Separate fields and values
d <- d[grep(":", d$V1),]
d <- cbind( 
  do.call( rbind, strsplit(d$V1, ":\\s+") ), 
  do.call( rbind, strsplit(d$V2, ":\\s+") ) 
)

# Add an id column
d <- cbind( d, cumsum( d[,1] == "Username" ) )

# Stack the left and right parts
d <- rbind( d[,c(5,1,2)], d[,c(5,3,4)] )
colnames(d) <- c("id", "field", "value")
d <- as.data.frame(d)
d$value <- gsub("\\s+$", "", d$value)

# Convert to a wide data.frame
library(reshape2)
d <- dcast( d, id ~ field )

答案 1 :(得分:2)

这些只是我如何解决问题的指导原则。我确信这是一种更奇特的方式。可能包括plyr。 :)

rara <- readLines("test.txt") # you could use readLines(textConnection = "text"))

# find usernames
usn <- rara[grepl("Username:", rara)]
# you can find a fancy way to split or weed out spaces
# I crudely do it like this:
unlist(lapply(strsplit(usn, "      "), "[", 2)) # 2 means "extract the second element"

# and accounts
acc <- rara[grepl("Account:", rara)]
unlist(lapply(strsplit(acc, "      "), "[", 2))

您可以使用str_trim()删除单词之前/之后的空格。希望有足够的指示让你前进。

答案 2 :(得分:2)

这是一个Powershell解决方案:

$result = @()

get-content c:\somedir\somefile.txt |
foreach {
    if ($_ -match '^Username:\s+(\S+)'){
        $rec = ""|select UserName,FinishTime,StartTime
        $rec.UserName = $matches[1]
        }
    elseif ($_ -match '^Account.+Finish\stime:\s+(.+)'){
        $rec.FinishTime = $matches[1]
        }
    elseif ($_ -match '^Process\sID:\s+\S+\s+Start\stime:\s+(.+)'){
        $rec.StartTime = $matches[1]
        $result += $rec
        }
}
$result

答案 3 :(得分:0)

您的文件是否在数据框中?与列名称一样,用户名,进程ID,开始时间......如果是,您可以通过

轻松提取它
df$Username (where df is your data frame and if you want to see all your usernames)
df$FinishTime

如果您想了解具有特定名称的用户的所有信息,请使用此

df[df$username == "SOMETHI",]

如果您想了解完成时间的用户..

希望这可以作为一个起点。如果不清楚,请告诉我。