基于与其他列匹配的部分字符串在数据框中创建新列

Question

我有2列的数据帧GL,并GLDESC与要添加一个名为第三列KIND基于一些数据是列内GLDESC.

数据框如下:

      GL                             GLDESC
1 515100         Payroll-Indir Salary Labor
2 515900 Payroll-Indir Compensated Absences
3 532300                           Bulk Gas
4 539991                     Area Charge In
5 551000        Repairs & Maint-Spare Parts
6 551100                 Supplies-Operating
7 551300                        Consumables

对于数据表的每一行:

• 如果在字符串GLDESC中的Payroll任何地方包含单词,那么我想KIND成为Payroll
• 如果在字符串GLDESC中的Gas任何地方包含单词,那么我想KIND成为Materials
• 在其他所有情况下我都想KIND成为Other

我在stackoverflow上找了类似的例子,但找不到任何东西,也查看了R开关上的假人,grep,apply和正则表达式尝试匹配GLDESC列的一部分,然后填充KIND列的帐户类型但是无法让它起作用.

Answer 1

由于您只有两个条件,因此可以使用嵌套ifelse:

#random data; it wasn't easy to copy-paste yours  
DF <- data.frame(GL = sample(10), GLDESC = paste(sample(letters, 10), 
  c("gas", "payroll12", "GaSer", "asdf", "qweaa", "PayROll-12", 
     "asdfg", "GAS--2", "fghfgh", "qweee"), sample(letters, 10), sep = " "))

DF$KIND <- ifelse(grepl("gas", DF$GLDESC, ignore.case = T), "Materials", 
         ifelse(grepl("payroll", DF$GLDESC, ignore.case = T), "Payroll", "Other"))

DF
#   GL         GLDESC      KIND
#1   8        e gas l Materials
#2   1  c payroll12 y   Payroll
#3  10      m GaSer v Materials
#4   6       t asdf n     Other
#5   2      w qweaa t     Other
#6   4 r PayROll-12 q   Payroll
#7   9      n asdfg a     Other
#8   5     d GAS--2 w Materials
#9   7     s fghfgh e     Other
#10  3      g qweee k     Other

编辑 2016年10月3日 (..after得到更多的关注于预期)

处理更多模式的可能解决方案可能是迭代所有模式,并且只要匹配,就逐渐减少比较量:

ff = function(x, patterns, replacements = patterns, fill = NA, ...)
{
    stopifnot(length(patterns) == length(replacements))

    ans = rep_len(as.character(fill), length(x))    
    empty = seq_along(x)

    for(i in seq_along(patterns)) {
        greps = grepl(patterns[[i]], x[empty], ...)
        ans[empty[greps]] = replacements[[i]]  
        empty = empty[!greps]
    }

    return(ans)
}

ff(DF$GLDESC, c("gas", "payroll"), c("Materials", "Payroll"), "Other", ignore.case = TRUE)
# [1] "Materials" "Payroll"   "Materials" "Other"     "Other"     "Payroll"   "Other"     "Materials" "Other"     "Other"

ff(c("pat1a pat2", "pat1a pat1b", "pat3", "pat4"), 
   c("pat1a|pat1b", "pat2", "pat3"), 
   c("1", "2", "3"), fill = "empty")
#[1] "1"     "1"     "3"     "empty"

ff(c("pat1a pat2", "pat1a pat1b", "pat3", "pat4"), 
   c("pat2", "pat1a|pat1b", "pat3"), 
   c("2", "1", "3"), fill = "empty")
#[1] "2"     "1"     "3"     "empty"