如何根据 R 中的其他列值将值放入列中

Question

我正在使用 R 为我作为记者的工作抓取和清理数据。我可以获得 HTML 的 table，然后将其作为数据框读取并重命名列的名称。现在我正在尝试创建一个新列，该列获取一个考虑到其他列值的值。

这个新列应该得到 "Avante"、"DEM"、"MDB"、"Patriota"、"PCdoB" 等的值。这是每个代表的聚会。比如Avante，有3个副手，分别是"Adalberto Cavalcanti"、"Cabo Sabino"和"Silvio Costa"。人大代表的名字总是在党名整排的下面。

url <- "http://www.camara.leg.br/internet/votacao/mostraVotacao.asp?ideVotacao=8559&numLegislatura=55&codCasa=1&numSessaoLegislativa=4&indTipoSessaoLegislativa=O&numSessao=225&indTipoSessao=E&tipo=partido"

library(xml2)
library(rvest)
file <- read_html(url)
tables <- html_nodes(file, "table")
table1 <- html_table(tables[3], fill = TRUE, header = T)

head(table1)

table1_df <- as.data.frame(table1)

colnames(table1_df) <- c("deputado", "uf", "voto")

这是我现在拥有的： enter image description here

这就是我想要的： enter image description here

Answer 1

这是一个只使用 base R 的解决方案：

url <- "http://www.camara.leg.br/internet/votacao/mostraVotacao.asp?ideVotacao=8559&numLegislatura=55&codCasa=1&numSessaoLegislativa=4&indTipoSessaoLegislativa=O&numSessao=225&indTipoSessao=E&tipo=partido"

library(xml2)
library(rvest)
file <- read_html(url)
tables <- html_nodes(file, "table")
table1 <- html_table(tables[3], fill = TRUE, header = T)

head(table1)

table1_df <- as.data.frame(table1)

colnames(table1_df) <- c("deputado", "uf", "voto")

# create the new column for later
table1_df$new_column <- NA

# identify rows with the Total PARTY: NUM rows
idx <- grep("Total.*: \d+", table1_df$deputado)

# Loop over these and assign the values
for (i in seq_along(idx)){
  # Extract the number of deputados
  n <- as.numeric(sub("^.*: ", "", table1_df$deputado[idx[i]]))
  # Extract the party
  partido <- sub("Total ", "", table1_df$deputado[idx[i]])
  partido <- sub(": .*", "", partido)
  # Assign the values
  table1_df$new_column[(idx[i] - n):(idx[i] - 1)] <- partido
}

# Remove the unnecessary lines
table1_df <- table1_df[-grep("Total .*:.*", table1_df$deputado), ]
table1_df <- table1_df[-which(table1_df$deputado == table1_df$uf), ]

Answer 2

这是另一个使用 zoo 和 dplyr 的选项。

1) 获取当事人姓名

parties <- sub(pattern = "Total\s(.+):\s\d+", 
                replacement = "\1", 
                x = table1_df$deputado[grepl("Total", x = table1_df$deputado)])

2) 添加 parties 作为新列，并在前面进行最后的观察，因为 parties[match(table1_df$deputado, parties)].

中有许多 NA

table1_df$new_col <- zoo::na.locf(parties[match(table1_df$deputado, parties)])

3) 删除不需要的行。

library(dplyr)
table1_df <- table1_df %>% 
  group_by(new_col) %>% 
  slice(2:(n()-1))
table1_df
# A tibble: 324 x 4
# Groups:   new_col [24]
#   deputado             uf    voto      new_col
#   <chr>                <chr> <chr>     <chr>  
# 1 Adalberto Cavalcanti PE    Não       Avante 
# 2 Cabo Sabino          CE    Abstenção Avante 
# 3 Silvio Costa         PE    Sim       Avante 
# 4 Alan Rick            AC    Sim       DEM    
# 5 Alberto Fraga        DF    Não       DEM    
# 6 Alexandre Leite      SP    Sim       DEM    
# 7 Arthur Oliveira Maia BA    Sim       DEM    
# 8 Carlos Melles        MG    Sim       DEM    
# 9 Efraim Filho         PB    Não       DEM    
#10 Eli Corrêa Filho     SP    Sim       DEM    
# ... with 314 more rows

如何根据 R 中的其他列值将值放入列中

How to put values inside a column based on other column values in R

r

dplyr

data-cleaning

rvest

tidyverse