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从R中的字符串向量提取城市

geocoding r

Marco C · 技术社区 · 8 年前

我的数据集db中有一列,比如db$affiliation,看起来像:

**db$affiliation**
[1] "[SCOTT, ALLEN J.] UNIV CALIF LOS ANGELES, DEPT GEOG, LOS ANGELES, CA 90095 USA"                               
[2] "[VAN DUINEN, RIANNE; VAN DER VEEN, ANNE] UNIV TWENTE, DEPT WATER ENGN & MANAGEMENT, DRIENERLOLAAN 5,POB 217, NL-7500 AE ENSCHEDE, NETHERLANDS."                                                
[3] "[ANANTSUKSOMSRI, SUTEE] CHULALONGKORN UNIV, FAC ARCHITECTURE, BANGKOK, THAILAND."   
[4] ...

我想在同一个数据集中创建一列,只包含db$affiliation中的城市名称,例如

 **db$cities**
 [1] LOS ANGELES
 [2] TWENTE
 [3] BANGKOK
 [4] ...

如果有多个城市名称可用,我希望命令只返回最后一个城市名称,如果没有城市名称可用,我希望使用NA。我该怎么做?

我想我可以 world.cities$name 在里面 data(world.cities) 在 maps 但我想不出是怎么回事。

我甚至尝试拆分db$附属列,例如:

db$affiliation <- gsub("\\[[^\\]]*\\]", "", db$affiliation, perl=TRUE) # remove content within brackets 
db$affiliation[2] # check the separator
db <- cSplit(db, 'affiliation', sep=c(", "), type.convert=FALSE) # split after comma

其结果(我在affiliation\u 3之后将其截断)为:

    affiliation_1            affiliation_2                  affiliation_3 
[1] UNIV CALIF LOS ANGELES   DEPT GEOG                      LOS ANGELES  
[2] UNIV TWENTE              DEPT WATER ENGN & MANAGEMENT   DRIENERLOLAAN            
[3] CHULALONGKORN UNIV       FAC ARCHITECTURE               BANGKOK

然后通过:

db$cities <- lapply(db$affiliation_1, function(x)x[which(x %in% world.cities$name)])

但我得到一个空列。

谢谢你的帮助!

3 回复 | 直到 8 年前

Prem 8 年前

示例字符串中有许多城市,如果在中发现多个城市,您可能需要重新考虑是否仍要获取“最后一个城市” affiliation 柱

library(maps)
data(world.cities)

#sample data
df <- data.frame(affiliation = c("[SCOTT, ALLEN J.] UNIV CALIF LOS ANGELES, DEPT GEOG, LOS ANGELES, CA 90095 USA",
                                 "[VAN DUINEN, RIANNE; VAN DER VEEN, ANNE] UNIV TWENTE, DEPT WATER ENGN & MANAGEMENT, DRIENERLOLAAN 5,POB 217, NL-7500 AE ENSCHEDE, NETHERLANDS.",
                                 "[ANANTSUKSOMSRI, SUTEE] CHULALONGKORN UNIV, FAC ARCHITECTURE, BANGKOK, THAILAND.",
                                 "Prem"), stringsAsFactors = F)

#fetch city and it's respective country from 'affiliation' column
cities_country <- lapply(gsub("\\[|\\]|[,;]|\\.","",df$affiliation), function(x) 
  paste(as.character(world.cities$name[sapply(world.cities$name, grepl, x, ignore.case=T)]),
        as.character(world.cities$country.etc[sapply(world.cities$name, grepl, x, ignore.case=T)]),
        sep="_"))
df$cities_country <- lapply(cities_country, function(x) if(identical(x, character(0))) NA_character_ else x)
df

输出为:

affiliation
1                                                                 [SCOTT, ALLEN J.] UNIV CALIF LOS ANGELES, DEPT GEOG, LOS ANGELES, CA 90095 USA
2 [VAN DUINEN, RIANNE; VAN DER VEEN, ANNE] UNIV TWENTE, DEPT WATER ENGN & MANAGEMENT, DRIENERLOLAAN 5,POB 217, NL-7500 AE ENSCHEDE, NETHERLANDS.
3                                                               [ANANTSUKSOMSRI, SUTEE] CHULALONGKORN UNIV, FAC ARCHITECTURE, BANGKOK, THAILAND.
4                                                                                                                                           Prem
                                                                                                                                                                                                                                                                                            cities_country
1                                                                      Al_Norway, Alle_Switzerland, Allen_Philippines, Allen_USA, Angeles_Costa Rica, Angeles_Philippines, Cali_Colombia, Cot_Costa Rica, Li_Norway, Los Angeles_Chile, Los Angeles_USA, Os_Kyrgyzstan, Os_Norway, U_Micronesia, Usa_Japan
2 Ae_Marshall Islands, Ede_Netherlands, Ede_Nigeria, Enschede_Netherlands, Hede_China, Ine_Marshall Islands, Laa_Austria, Lola_Guinea, Man_Ivory Coast, Mana_French Guiana, Manage_Belgium, Nagem_Luxembourg, Ob_Russia, Ola_Panama, Po_Burkina Faso, U_Micronesia, Van_Turkey, Wa_Ghana, We_New Caledonia
3                                                                                                                                     Aila_Estonia, Al_Norway, Anan_Japan, Ba_Fiji, Bangkok_Thailand, Hit_Iraq, Ila_Nigeria, Ilan_Taiwan, Long_Thailand, Nan_Thailand, Tsu_Japan, U_Micronesia, Ula_Turkey
4                                                                                                                                                                                                                                                                                                       NA

( 笔记在上述输出中,我保留了所有出现的城市,并且为了方便起见,还将其加上了各自国家的后缀)

RolandASc 8 年前

从您显示的几行中可以看出,您可能可以执行以下操作(请注意,您没有对齐套管):

tmpVec <- sapply(strsplit(db$affiliation, split = ","), function(x) {
  cleanVec <- toupper(trimws(x))
  cleanVec[max(which(cleanVec %in% toupper(maps::world.cities$name)))]
})

或者在函数中添加更多代码,以避免出现难看的警告。

jazzurro 8 年前

让我留下解决方案的一部分。根据我自己的研究,方括号中的字母似乎表示个人姓名。例如,我发现 Sutee Anantsuksomsri 是实际名称。这一观察结果表明,我们可能希望删除括号中的文本。

删除方括号中的文本后,我使用 unnest_tokens() 在tidytext包中。请注意,该函数将所有字母转换为小写字母。如果不喜欢,可以通过指定 to_lower = FALSE . 首先,我把每个城市的名字分成几个单词。我还为每个城市分配了一个ID号。其次,我清理了你的数据。如前所述,我使用 gsub() . 然后,我申请了 unnest\u令牌() 到数据。我使用来自 cities 在里面 filter() . 到目前为止,我们得到的结果如下。显然,你还有更多的工作要做。我留下了采样数据, mydf 在下面我希望你能离开这里。

data(world.cities)

cities <- world.cities %>%
          mutate(id = 1:n()) %>%
          unnest_tokens(input = name, output = word, token = "words")

temp <- mydf %>%
        mutate(affiliation = gsub(x = affiliation, pattern = "\\[.*\\]", replacement = "")) %>%          
        unnest_tokens(input = affiliation, output = word, token = "words") %>%
        filter(word %in% cities$word)


   id     word
1   1      los
2   1  angeles
3   1      los
4   1  angeles
5   1       ca
6   1      usa
7   2    water
8   2       ae
9   2 enschede
10  3  bangkok

数据

mydf <- structure(list(id = 1:3, affiliation = c("[SCOTT, ALLEN J.] UNIV CALIF LOS ANGELES, DEPT GEOG, LOS ANGELES, CA 90095 USA", 
"[VAN DUINEN, RIANNE; VAN DER VEEN, ANNE] UNIV TWENTE, DEPT WATER ENGN & MANAGEMENT, DRIENERLOLAAN 5,POB 217, NL-7500 AE ENSCHEDE, NETHERLANDS.", 
"[ANANTSUKSOMSRI, SUTEE] CHULALONGKORN UNIV, FAC ARCHITECTURE, BANGKOK, THAILAND."
)), .Names = c("id", "affiliation"), row.names = c(NA, -3L), class = "data.frame")