Come elencare i file per data in r (con esempio)
È possibile utilizzare la seguente sintassi di base per elencare i file nella directory di lavoro corrente in R per data:
#extract all CSV files in working directory file_info = file. info ( list.files (pattern=" *.csv ")) #sort files based on mtime (date and time modification) file_info = file_info[ with (file_info, order (as. POSIXct (mtime))), ] #view only file names with modification date and time file_info[c(" mtime ")]
L’esempio seguente mostra come utilizzare questa sintassi nella pratica.
Esempio: come elencare i file per data in R
Supponiamo di voler elencare tutti i file CSV nella directory di lavoro corrente in R per data.
Posso utilizzare la seguente sintassi per estrarre prima tutti i file CSV (con le informazioni sui file) dalla directory di lavoro corrente:
#extract all CSV files in working directory file_info = file. info ( list.files (pattern=" *.csv ")) #view all CSV files file_info size isdir mode mtime ctime atime exe basketball_data.csv 55 FALSE 666 2023-01-06 11:07:43 2022-07-12 09:07:26 2023-04-18 09:42:19 no df1.csv 126 FALSE 666 2022-04-21 10:48:24 2022-04-21 10:48:24 2023-04-18 09:42:19 no df2.csv 126 FALSE 666 2022-04-21 10:48:30 2022-04-21 10:48:29 2023-04-18 09:42:19 no df3.csv 126 FALSE 666 2022-04-21 10:48:34 2022-04-21 10:48:34 2023-04-18 09:42:19 no my_data.csv 53 FALSE 666 2022-09-09 09:02:21 2022-04-22 09:00:13 2023-04-18 09:42:19 no my_list.csv 90 FALSE 666 2022-04-21 09:40:01 2022-04-21 09:39:59 2023-04-18 09:42:19 no my_test.csv 146 FALSE 666 2022-04-21 09:42:25 2022-04-21 09:42:25 2023-04-18 09:42:19 no player_stats.csv 137 FALSE 666 2023-04-11 09:07:20 2023-04-11 09:07:20 2023-04-18 09:42:19 no players_data.csv 50 FALSE 666 2023-01-06 09:44:12 2023-01-06 09:44:12 2023-04-18 09:42:19 no team_info.csv 131 FALSE 666 2023-04-11 09:07:21 2023-04-11 09:07:21 2023-04-18 09:42:19 no test.csv 18059168 FALSE 666 2022-09-07 09:07:34 2020-02-01 13:44:03 2023-04-18 09:42:19 no uneven_data.csv 43 FALSE 666 2023-01-06 14:02:17 2023-01-06 14:00:27 2023-04-18 09:42:19 no
Posso quindi utilizzare la funzione order() per ordinare i file in base a mtime , che rappresenta la data e l’ora dell’ultima modifica dei file:
#sort files based on mtime (date and time modification) file_info = file_info[ with (file_info, order (as. POSIXct (mtime))), ] #view sorted files file_info size isdir mode mtime ctime atime exe my_list.csv 90 FALSE 666 2022-04-21 09:40:01 2022-04-21 09:39:59 2023-04-18 09:42:19 no my_test.csv 146 FALSE 666 2022-04-21 09:42:25 2022-04-21 09:42:25 2023-04-18 09:42:19 no df1.csv 126 FALSE 666 2022-04-21 10:48:24 2022-04-21 10:48:24 2023-04-18 09:42:19 no df2.csv 126 FALSE 666 2022-04-21 10:48:30 2022-04-21 10:48:29 2023-04-18 09:42:19 no df3.csv 126 FALSE 666 2022-04-21 10:48:34 2022-04-21 10:48:34 2023-04-18 09:42:19 no test.csv 18059168 FALSE 666 2022-09-07 09:07:34 2020-02-01 13:44:03 2023-04-18 09:42:19 no my_data.csv 53 FALSE 666 2022-09-09 09:02:21 2022-04-22 09:00:13 2023-04-18 09:42:19 no players_data.csv 50 FALSE 666 2023-01-06 09:44:12 2023-01-06 09:44:12 2023-04-18 09:42:19 no basketball_data.csv 55 FALSE 666 2023-01-06 11:07:43 2022-07-12 09:07:26 2023-04-18 09:42:19 no uneven_data.csv 43 FALSE 666 2023-01-06 14:02:17 2023-01-06 14:00:27 2023-04-18 09:42:19 no player_stats.csv 137 FALSE 666 2023-04-11 09:07:20 2023-04-11 09:07:20 2023-04-18 09:42:19 no team_info.csv 131 FALSE 666 2023-04-11 09:07:21 2023-04-11 09:07:21 2023-04-18 09:42:19 no
Tieni presente che puoi invece utilizzare ctime se desideri ordinare i file in base alla data di creazione o atime per ordinare i file in base alla data di accesso .
Infine, possiamo sottoimpostare il frame di dati per visualizzare solo i nomi dei file e la data e l’ora dell’ultima modifica:
#view only file names with modification date and time file_info[c(" mtime ")] mtime my_list.csv 2022-04-21 09:40:01 my_test.csv 2022-04-21 09:42:25 df1.csv 2022-04-21 10:48:24 df2.csv 2022-04-21 10:48:30 df3.csv 2022-04-21 10:48:34 test.csv 2022-09-07 09:07:34 my_data.csv 2022-09-09 09:02:21 players_data.csv 2023-01-06 09:44:12 basketball_data.csv 2023-01-06 11:07:43 uneven_data.csv 2023-01-06 14:02:17 player_stats.csv 2023-04-11 09:07:20 team_info.csv 2023-04-11 09:07:21
Se lo desideri, puoi anche visualizzare solo i nomi dei file per data:
#view only file names
rownames(file_info)
[1] "my_list.csv" "my_test.csv" "df1.csv" "df2.csv" "df3.csv"
[6] "test.csv" "my_data.csv" "players_data.csv" "basketball_data.csv" "uneven_data.csv"
[11] "player_stats.csv" "team_info.csv"
I dodici nomi di file CSV sono ordinati per data.
Correlato: Come utilizzare la funzione list.files() in R (4 esempi)
Risorse addizionali
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