le code ci-dessous me permet d'obtenir les moyennes selon 2 arguments qui sont des colonnes.
Code : Tout sélectionner
mean_donnees <- do.call(
what = "data.frame",
args = aggregate(
x = donnees[4],
by = donnees[c("voie","time")],
FUN = function(x) mean = mean(x, na.rm = TRUE)
))
mean_sd_donnees <- arrange(mean_sd_donnees, by=voie)
Je souhaiterai ajouter un critère supplémentaire pour moyenner seulement les 2 derniers valeurs et non toutes celles selectionnées via "by = donnees[c("voie","time")]"
Les données utilisées :
Code : Tout sélectionner
donnees<-data.frame(
timestamp = c(
"2022-01-03 03:00:00","2022-01-03 03:10:00","2022-01-03 03:20:00","2022-01-03 03:30:00",
"2022-01-03 03:40:00","2022-01-03 03:50:00","2022-01-03 04:00:00","2022-01-03 04:10:00",
"2022-01-03 04:20:00","2022-01-03 04:30:00","2022-01-03 04:40:00","2022-01-03 04:50:00",
"2022-01-03 05:00:00","2022-01-03 05:10:00","2022-01-03 05:20:00","2022-01-03 05:30:00",
"2022-01-03 05:00:00","2022-01-03 05:10:00","2022-01-03 05:20:00","2022-01-03 05:30:00"
),
voie = c(
"B_1","B_1","B_1","B_1","B_1","B_1","B_1","B_1","B_1","B_1","B_2","B_2","B_2","B_2","B_2","B_2","B_2","B_2","B_2","B_2"),
time = c(0,100,100,100,200,200,200,300,300,300,0,100,100,100,200,200,200,300,300,300),
Temp = c(1,1,6,7,1,1,8,9,1,1,6,7,1,1,4,8,5,7,2,5))
Je vous remercie par avance.