自分のためのR小技集

自分用のメモです。

TRUE/FALSEの数を数えたい

> a = c(TRUE, TRUE, FALSE, TRUE, FALSE)
> sum(a) 
[1] 3

> b <- data.frame(x=c(1, 2, 3, NA), y=c(NA, 4, 5, NA), z=c(6, 7, 8, 9))
> table(is.na(b))

FALSE  TRUE 
    9     3

データセットから特定のIDのデータをomit

> df = data.frame(ID = c("ID1","ID2","ID3","ID4","ID5","ID6","ID7"), 
                 score1=c(4,6,2,9,5,7,8),
                 score2=c(45,78,44,89,66,49,72),
                 score3=c(56,52,45,88,33,90,47))
> df
   ID score1 score2 score3
1 ID1      4     45     56
2 ID2      6     78     52
3 ID3      2     44     45
4 ID4      9     89     88
5 ID5      5     66     33
6 ID6      7     49     90
7 ID7      8     72     47
>
> omit_ID <- c("ID2","ID3","ID6") 
> df2 <- df[is.na(match(df$ID,omit_ID)==FALSE),]
> df2
  ID score1 score2 score3
1  1      4     45     56
4  4      9     89     88
5  5      5     66     33
7  7      8     72     47

データセットから特定列に特定キーワードを含む行をomit(大文字小文字も無視)

> df
  ID        score1 score2 score3
1  1           Yes     45     56
2  2            No     78     52
3  3     Maybe yes     44     45
4  4            No     89     88
5  5  No Thank you     66     33
6  6      Yes I do     49     90
7  7 of course Yes     72     47
>
> df2 <- df %>% filter(!grepl("yes",score1,ignore.case=TRUE))
> df2
  ID       score1 score2 score3
1  2           No     78     52
2  4           No     89     88
3  5 No Thank you     66     33

特定列の列名変更

> df
  ID        score1 score2 score3
1  1           Yes     45     56
2  2            No     78     52
3  3     Maybe yes     44     45
4  4            No     89     88
5  5  No Thank you     66     33
6  6      Yes I do     49     90
7  7 of course Yes     72     47
>
> df <- dplyr::select(df, No = ID, dplyr::everything())
> df
   No score4 score1 score2
1 ID1     56      4     45
2 ID2     52      6     78
3 ID3     45      2     44
4 ID4     88      9     89
5 ID5     33      5     66
6 ID6     90      7     49
7 ID7     47      8     72