あなたは、このようなデータを扱っていると仮定:
mydf <- structure(list(author.ID = c(1L, 1L, 2L), coauthor.names = c("J Smith, A Greer",
"J Adams, J Smith", "D Richardson, J Smith")), .Names = c("author.ID",
"coauthor.names"), row.names = c(NA, 3L), class = "data.frame")
mydf
## author.ID coauthor.names
## 1 1 J Smith, A Greer
## 2 1 J Adams, J Smith
## 3 2 D Richardson, J Smith
...あなたは私の "splitstackshape" パッケージからcSplit
を試してみて、それから "data.table" から.N
に集約することができます
library(splitstackshape)
cSplit(mydf, "coauthor.names", ",", "long")[
, list(collaboaration.times = .N), .(author.ID, coauthor.names)][]
# author.ID coauthor.names collaboaration.times
# 1: 1 J Smith 2
# 2: 1 A Greer 1
# 3: 1 J Adams 1
# 4: 2 D Richardson 1
# 5: 2 J Smith 1
あなたは、このようなデータを扱っていると仮定:
mydf2 <- structure(list(author.ID = c(1L, 1L, 2L), coauthor.names = structure(list(
c("J Smith", "A Greer"), c("J Adams", "J Smith"), c("D Richardson",
"J Smith")), class = "AsIs")), .Names = c("author.ID", "coauthor.names"
), row.names = c(NA, 3L), class = "data.frame")
mydf2
## author.ID coauthor.names
## 1 1 J Smith,....
## 2 1 J Adams,....
## 3 2 D Richar....
... listCol_l
(やはり "splitstackshape"から)で始まり、同様にカウントできます。
listCol_l(mydf2, "coauthor.names")[
, list(collaboration.times = .N), .(author.ID, coauthor.names_ul)]
# author.ID coauthor.names_ul collaboration.times
# 1: 1 J Smith 2
# 2: 1 A Greer 1
# 3: 1 J Adams 1
# 4: 2 D Richardson 1
# 5: 2 J Smith 1
"tidyverse" 同等物は、このようなものかもしれません:
library(tidyverse)
# For a single character string as "coauthor.names"
mydf %>%
mutate(coauthor.names = lapply(strsplit(coauthor.names, ","), trimws)) %>%
unnest() %>%
group_by(author.ID, coauthor.names) %>%
summarise(collaboration.times = n())
# If "coauthor.names" is already a `list`.
mydf2 %>%
unnest() %>%
group_by(author.ID, coauthor.names) %>%
summarise(collaboration.times = n())
ありがとうございました。今私は進めることができます! – Waht