Welche Umformprobleme lassen sich durch Schmelzen/Gießen nicht in einem Schritt lösen?
https://stackoverflow.com//questions/10675031
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reshape2 ist ein Paket, das durch seinen zweiteiligen Schmelz-/Guss-Ansatz eine Reihe leistungsstarker Datentransformationen ermöglicht.Wie bei allen Tools sind jedoch Annahmen verankert, die die Fälle, mit denen es umgehen kann, einschränken.
Welches Problem kann die Datenumformung haben? reshape2 nicht in der jetzigen Form handhabbar?
Die ideale Antwort umfasst:
- Eine Beschreibung der Art von Anwendungsfällen, in denen diese Datenform typischerweise vorkommt
- Beispieldaten
- Code zum Durchführen der Transformation (idealerweise unter Verwendung eines möglichst großen Teils der Transformation).
reshape2wie möglich)
Beispiel
„Breite“ Daten sind bei Panel-Anwendungen üblich.
melt.wide <- function(data, id.vars, new.names, sep=".", variable.name="variable", ... ) {
# Guess number of variables currently wide
colnames(data) <- sub( paste0(sep,"$"), "", colnames(data) )
wide.vars <- colnames(data)[grep( sep, colnames(data) )]
n.wide <- str_count( wide.vars, sep )
stopifnot(length(new.names)==unique(n.wide))
# Melt
data.melt <- melt(data,id.vars=id.vars,measure.vars=wide.vars,...)
new <- stack.list(str_split(data.melt$variable,sep))
colnames(new) <- c(variable.name,new.names)
data.melt <- subset(data.melt,select=c(-variable))
cbind(data.melt,new)
}
choice.vars <- colnames(res)[grep("_",colnames(res))]
melt.wide( subset(res,select=c("WorkerId",choice.vars)), id.vars="WorkerId", new.names=c("set","option"), sep="_")
Die neue Funktion gibt ein geschmolzenes Objekt zurück, das dann sein kann *cast.
Wo sind die Daten:
so <- structure(list(WorkerId = c(12L, 13L, 27L, 25L, 30L, 8L), pio_1_1 = structure(c(2L,
1L, 2L, 1L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
pio_1_2 = structure(c(1L, 2L, 2L, 2L, 1L, 1L), .Label = c("No",
"Yes"), class = "factor"), pio_1_3 = structure(c(1L, 1L,
1L, 1L, 2L, 1L), .Label = c("No", "Yes"), class = "factor"),
pio_1_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"),
pio_2_1 = structure(c(1L, 2L, 2L, 1L, 1L, 2L), .Label = c("No",
"Yes"), class = "factor"), pio_2_2 = structure(c(1L, 1L,
1L, 2L, 1L, 1L), .Label = c("No", "Yes"), class = "factor"),
pio_2_3 = structure(c(2L, 2L, 2L, 2L, 2L, 1L), .Label = c("No",
"Yes"), class = "factor"), pio_2_4 = structure(c(1L, 1L,
1L, 1L, 1L, 1L), .Label = "No", class = "factor"), pio_3_1 = structure(c(2L,
2L, 2L, 2L, 2L, 1L), .Label = c("No", "Yes"), class = "factor"),
pio_3_2 = structure(c(2L, 1L, 1L, 1L, 2L, 1L), .Label = c("No",
"Yes"), class = "factor"), pio_3_3 = structure(c(2L, 1L,
2L, 1L, 1L, 2L), .Label = c("No", "Yes"), class = "factor"),
pio_3_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"),
pio_4_1 = structure(c(2L, 1L, 2L, 2L, 1L, 2L), .Label = c("No",
"Yes"), class = "factor"), pio_4_2 = structure(c(2L, 2L,
2L, 1L, 2L, 1L), .Label = c("No", "Yes"), class = "factor"),
pio_4_3 = structure(c(1L, 2L, 1L, 1L, 2L, 2L), .Label = c("No",
"Yes"), class = "factor"), pio_4_4 = structure(c(1L, 1L,
1L, 1L, 1L, 1L), .Label = "No", class = "factor"), caremgmt_1_1 = structure(c(2L,
2L, 1L, 2L, 1L, 2L), .Label = c("No", "Yes"), class = "factor"),
caremgmt_1_2 = structure(c(1L, 2L, 2L, 2L, 1L, 1L), .Label = c("No",
"Yes"), class = "factor"), caremgmt_1_3 = structure(c(1L,
1L, 1L, 1L, 2L, 1L), .Label = c("No", "Yes"), class = "factor"),
caremgmt_1_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"),
caremgmt_2_1 = structure(c(2L, 2L, 2L, 2L, 2L, 2L), .Label = c("No",
"Yes"), class = "factor"), caremgmt_2_2 = structure(c(1L,
2L, 1L, 2L, 1L, 1L), .Label = c("No", "Yes"), class = "factor"),
caremgmt_2_3 = structure(c(2L, 1L, 2L, 1L, 1L, 1L), .Label = c("No",
"Yes"), class = "factor"), caremgmt_2_4 = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"), caremgmt_3_1 = structure(c(2L,
1L, 2L, 1L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
caremgmt_3_2 = structure(c(2L, 1L, 2L, 2L, 2L, 1L), .Label = c("No",
"Yes"), class = "factor"), caremgmt_3_3 = structure(c(2L,
2L, 2L, 2L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
caremgmt_3_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"),
caremgmt_4_1 = structure(c(1L, 1L, 2L, 1L, 2L, 1L), .Label = c("No",
"Yes"), class = "factor"), caremgmt_4_2 = structure(c(2L,
2L, 2L, 2L, 1L, 1L), .Label = c("No", "Yes"), class = "factor"),
caremgmt_4_3 = structure(c(1L, 1L, 1L, 1L, 1L, 2L), .Label = c("No",
"Yes"), class = "factor"), caremgmt_4_4 = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"), prev_1_1 = structure(c(1L,
1L, 2L, 1L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
prev_1_2 = structure(c(1L, 2L, 1L, 2L, 1L, 1L), .Label = c("No",
"Yes"), class = "factor"), prev_1_3 = structure(c(2L, 1L,
1L, 2L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
prev_1_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"),
prev_2_1 = structure(c(1L, 1L, 2L, 1L, 2L, 2L), .Label = c("No",
"Yes"), class = "factor"), prev_2_2 = structure(c(2L, 2L,
1L, 2L, 1L, 1L), .Label = c("No", "Yes"), class = "factor"),
prev_2_3 = structure(c(1L, 2L, 1L, 1L, 2L, 2L), .Label = c("No",
"Yes"), class = "factor"), prev_2_4 = structure(c(1L, 1L,
1L, 1L, 1L, 1L), .Label = "No", class = "factor"), prev_3_1 = structure(c(1L,
2L, 1L, 1L, 2L, 1L), .Label = c("No", "Yes"), class = "factor"),
prev_3_2 = structure(c(1L, 1L, 2L, 1L, 2L, 2L), .Label = c("No",
"Yes"), class = "factor"), prev_3_3 = structure(c(2L, 2L,
1L, 2L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
prev_3_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "No", class = "factor"),
prev_4_1 = structure(c(1L, 2L, 2L, 1L, 2L, 2L), .Label = c("No",
"Yes"), class = "factor"), prev_4_2 = structure(c(1L, 1L,
2L, 1L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"),
prev_4_3 = structure(c(1L, 1L, 1L, 2L, 2L, 1L), .Label = c("No",
"Yes"), class = "factor"), prev_4_4 = structure(c(1L, 1L,
1L, 1L, 1L, 1L), .Label = "No", class = "factor"), price_1_1 = structure(c(30L,
12L, 1L, 16L, 28L, 17L), .Label = c("$2,500", "$2,504", "$2,507",
"$2,509", "$2,512", "$2,513", "$2,515", "$2,526", "$2,547",
"$2,548", "$2,578", "$2,588", "$2,594", "$2,605", "$2,607",
"$2,617", "$2,618", "$2,622", "$2,635", "$2,649", "$2,670",
"$2,672", "$2,679", "$2,681", "$2,698", "$2,704", "$2,721",
"$2,782", "$2,851", "$2,884", "$2,919", "$2,925", "$2,935",
"$3,022"), class = "factor"), price_1_2 = structure(c(1L,
19L, 5L, 17L, 7L, 1L), .Label = c("$2,500", "$2,501", "$2,502",
"$2,504", "$2,513", "$2,515", "$2,517", "$2,532", "$2,535",
"$2,558", "$2,564", "$2,571", "$2,575", "$2,578", "$2,608",
"$2,633", "$2,634", "$2,675", "$2,678", "$2,687", "$2,730",
"$2,806", "$2,827", "$2,848", "$2,891", "$2,901", "$2,923",
"$2,933", "$2,937", "$2,958", "$2,987"), class = "factor"),
price_1_3 = structure(c(11L, 1L, 1L, 8L, 19L, 14L), .Label = c("$2,500",
"$2,504", "$2,507", "$2,513", "$2,516", "$2,518", "$2,564",
"$2,579", "$2,580", "$2,583", "$2,584", "$2,592", "$2,604",
"$2,608", "$2,639", "$2,643", "$2,646", "$2,665", "$2,667",
"$2,695", "$2,698", "$2,709", "$2,710", "$2,713", "$2,714",
"$2,750", "$2,757", "$2,876", "$2,978", "$2,984", "$3,024",
"$3,059"), class = "factor"), price_1_4 = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = "$2,500", class = "factor"),
price_2_1 = structure(c(27L, 32L, 19L, 22L, 4L, 26L), .Label = c("$2,500",
"$2,504", "$2,505", "$2,510", "$2,511", "$2,512", "$2,515",
"$2,517", "$2,518", "$2,529", "$2,533", "$2,537", "$2,551",
"$2,553", "$2,574", "$2,593", "$2,600", "$2,605", "$2,608",
"$2,612", "$2,613", "$2,618", "$2,639", "$2,657", "$2,714",
"$2,730", "$2,747", "$2,764", "$2,771", "$2,773", "$2,813",
"$2,859", "$2,901", "$3,019", "$3,037"), class = "factor"),
price_2_2 = structure(c(12L, 2L, 1L, 27L, 1L, 7L), .Label = c("$2,500",
"$2,502", "$2,510", "$2,514", "$2,515", "$2,516", "$2,517",
"$2,518", "$2,520", "$2,521", "$2,523", "$2,536", "$2,544",
"$2,575", "$2,583", "$2,592", "$2,602", "$2,624", "$2,644",
"$2,652", "$2,662", "$2,677", "$2,720", "$2,761", "$2,765",
"$2,770", "$2,772", "$2,835", "$2,873", "$2,911", "$2,950",
"$2,962"), class = "factor"), price_2_3 = structure(c(32L,
1L, 8L, 33L, 29L, 11L), .Label = c("$2,500", "$2,506", "$2,507",
"$2,510", "$2,511", "$2,512", "$2,515", "$2,517", "$2,527",
"$2,528", "$2,540", "$2,554", "$2,562", "$2,565", "$2,568",
"$2,581", "$2,597", "$2,611", "$2,616", "$2,631", "$2,652",
"$2,663", "$2,671", "$2,672", "$2,685", "$2,727", "$2,731",
"$2,742", "$2,771", "$2,778", "$2,781", "$2,970", "$2,984",
"$2,986", "$3,030"), class = "factor"), price_2_4 = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = "$2,500", class = "factor"),
price_3_1 = structure(c(24L, 1L, 28L, 7L, 18L, 21L), .Label = c("$2,500",
"$2,501", "$2,503", "$2,505", "$2,509", "$2,512", "$2,535",
"$2,537", "$2,542", "$2,553", "$2,556", "$2,560", "$2,561",
"$2,574", "$2,584", "$2,618", "$2,624", "$2,629", "$2,637",
"$2,664", "$2,761", "$2,840", "$2,875", "$2,883", "$2,891",
"$2,933", "$2,953", "$2,978", "$3,039", "$3,043", "$3,067"
), class = "factor"), price_3_2 = structure(c(3L, 1L, 5L,
19L, 25L, 9L), .Label = c("$2,500", "$2,501", "$2,503", "$2,504",
"$2,512", "$2,517", "$2,540", "$2,543", "$2,546", "$2,560",
"$2,567", "$2,573", "$2,586", "$2,592", "$2,594", "$2,603",
"$2,604", "$2,606", "$2,628", "$2,633", "$2,635", "$2,693",
"$2,696", "$2,714", "$2,734", "$2,739", "$2,770", "$2,791",
"$2,797", "$2,936", "$2,967", "$3,021", "$3,024"), class = "factor"),
price_3_3 = structure(c(26L, 7L, 5L, 32L, 10L, 24L), .Label = c("$2,500",
"$2,501", "$2,502", "$2,505", "$2,506", "$2,507", "$2,508",
"$2,509", "$2,512", "$2,515", "$2,519", "$2,547", "$2,556",
"$2,574", "$2,587", "$2,592", "$2,608", "$2,616", "$2,621",
"$2,635", "$2,638", "$2,667", "$2,671", "$2,688", "$2,694",
"$2,700", "$2,717", "$2,759", "$2,809", "$2,864", "$2,891",
"$2,912", "$3,011", "$3,012"), class = "factor"), price_3_4 = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = "$2,500", class = "factor"),
price_4_1 = structure(c(29L, 13L, 16L, 24L, 33L, 19L), .Label = c("$2,500",
"$2,505", "$2,506", "$2,508", "$2,511", "$2,525", "$2,549",
"$2,562", "$2,577", "$2,582", "$2,586", "$2,591", "$2,621",
"$2,636", "$2,654", "$2,670", "$2,722", "$2,726", "$2,733",
"$2,744", "$2,745", "$2,755", "$2,768", "$2,805", "$2,817",
"$2,827", "$2,835", "$2,888", "$2,925", "$2,959", "$3,001",
"$3,027", "$3,061", "$3,071"), class = "factor"), price_4_2 = structure(c(33L,
31L, 21L, 16L, 25L, 13L), .Label = c("$2,500", "$2,502",
"$2,503", "$2,505", "$2,506", "$2,511", "$2,513", "$2,516",
"$2,529", "$2,539", "$2,547", "$2,554", "$2,557", "$2,562",
"$2,567", "$2,579", "$2,581", "$2,583", "$2,585", "$2,591",
"$2,612", "$2,629", "$2,640", "$2,670", "$2,695", "$2,726",
"$2,737", "$2,788", "$2,790", "$2,798", "$2,852", "$3,031",
"$3,063"), class = "factor"), price_4_3 = structure(c(4L,
30L, 4L, 19L, 1L, 27L), .Label = c("$2,500", "$2,504", "$2,507",
"$2,509", "$2,511", "$2,512", "$2,514", "$2,516", "$2,543",
"$2,552", "$2,562", "$2,575", "$2,578", "$2,581", "$2,594",
"$2,614", "$2,615", "$2,617", "$2,636", "$2,640", "$2,641",
"$2,652", "$2,749", "$2,755", "$2,805", "$2,812", "$2,867",
"$2,906", "$2,910", "$2,917", "$2,924", "$2,927", "$2,961",
"$3,028", "$3,053", "$3,054"), class = "factor"), price_4_4 = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = "$2,500", class = "factor"),
plan_1_1 = structure(c(2L, 2L, 2L, 1L, 1L, 2L), .Label = c("",
"X"), class = "factor"), plan_1_2 = structure(c(1L, 1L, 1L,
2L, 1L, 1L), .Label = c("", "X"), class = "factor"), plan_1_3 = structure(c(1L,
1L, 1L, 1L, 2L, 1L), .Label = c("", "X"), class = "factor"),
plan_1_4 = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = c("",
"X"), class = "factor"), plan_2_1 = structure(c(1L, 2L, 1L,
2L, 2L, 2L), .Label = c("", "X"), class = "factor"), plan_2_2 = structure(c(1L,
1L, 2L, 1L, 1L, 1L), .Label = c("", "X"), class = "factor"),
plan_2_3 = structure(c(2L, 1L, 1L, 1L, 2L, 1L), .Label = c("",
"X"), class = "factor"), plan_2_4 = structure(c(1L, 1L, 1L,
1L, 1L, 1L), .Label = c("", "X"), class = "factor"), plan_3_1 = structure(c(1L,
2L, 1L, 1L, 2L, 1L), .Label = c("", "X"), class = "factor"),
plan_3_2 = structure(c(1L, 1L, 1L, 2L, 1L, 1L), .Label = c("",
"X"), class = "factor"), plan_3_3 = structure(c(2L, 1L, 1L,
1L, 1L, 2L), .Label = c("", "X"), class = "factor"), plan_3_4 = structure(c(1L,
1L, 2L, 1L, 1L, 1L), .Label = c("", "X"), class = "factor"),
plan_4_1 = structure(c(2L, 2L, 1L, 1L, 1L, 1L), .Label = c("",
"X"), class = "factor"), plan_4_2 = structure(c(2L, 1L, 1L,
2L, 1L, 1L), .Label = c("", "X"), class = "factor"), plan_4_3 = structure(c(1L,
1L, 1L, 1L, 2L, 2L), .Label = c("", "X"), class = "factor"),
plan_4_4 = structure(c(1L, 1L, 2L, 1L, 1L, 1L), .Label = c("",
"X"), class = "factor")), .Names = c("WorkerId", "pio_1_1",
"pio_1_2", "pio_1_3", "pio_1_4", "pio_2_1", "pio_2_2", "pio_2_3",
"pio_2_4", "pio_3_1", "pio_3_2", "pio_3_3", "pio_3_4", "pio_4_1",
"pio_4_2", "pio_4_3", "pio_4_4", "caremgmt_1_1", "caremgmt_1_2",
"caremgmt_1_3", "caremgmt_1_4", "caremgmt_2_1", "caremgmt_2_2",
"caremgmt_2_3", "caremgmt_2_4", "caremgmt_3_1", "caremgmt_3_2",
"caremgmt_3_3", "caremgmt_3_4", "caremgmt_4_1", "caremgmt_4_2",
"caremgmt_4_3", "caremgmt_4_4", "prev_1_1", "prev_1_2", "prev_1_3",
"prev_1_4", "prev_2_1", "prev_2_2", "prev_2_3", "prev_2_4", "prev_3_1",
"prev_3_2", "prev_3_3", "prev_3_4", "prev_4_1", "prev_4_2", "prev_4_3",
"prev_4_4", "price_1_1", "price_1_2", "price_1_3", "price_1_4",
"price_2_1", "price_2_2", "price_2_3", "price_2_4", "price_3_1",
"price_3_2", "price_3_3", "price_3_4", "price_4_1", "price_4_2",
"price_4_3", "price_4_4", "plan_1_1", "plan_1_2", "plan_1_3",
"plan_1_4", "plan_2_1", "plan_2_2", "plan_2_3", "plan_2_4", "plan_3_1",
"plan_3_2", "plan_3_3", "plan_3_4", "plan_4_1", "plan_4_2", "plan_4_3",
"plan_4_4"), row.names = c(NA, 6L), class = "data.frame")
Lösung
...fast ein Jahr später...
Das ist mir neulich in den Sinn gekommen, und ich habe den leisen Verdacht, dass es das ist, was Sie in Ihrem Beispiel zeigen wollten, aber leider läuft Ihr Beispielcode nicht!
melt Manchmal geht es mir etwas zu weit, wenn ich meine Daten „lang“ mache.Manchmal bevorzuge ich eine „halblange“ Datei, auch wenn es nicht unbedingt das ist, was man als „ordentliche Daten“ bezeichnen würde. data.frame.Dies lässt sich leicht mit Basis-Rs erreichen reshape, erfordert aber ein paar zusätzliche Schritte mit dem Paket „reshape2“, wie unten gezeigt:
Voraussetzung:Beispieldaten.
set.seed(1)
myDf <- data.frame(
ID.1 = sample(letters[1:5], 5, replace = TRUE),
ID.2 = 1:5,
V.1 = sample(10:14, 5, replace = TRUE),
V.2 = sample(5:9, 5, replace = TRUE),
V.3 = sample(3:14, 5, replace = TRUE),
W.1 = sample(LETTERS, 5, replace = TRUE),
W.2 = sample(LETTERS, 5, replace = TRUE),
W.3 = sample(LETTERS, 5, replace = TRUE)
)
myDf
# ID.1 ID.2 V.1 V.2 V.3 W.1 W.2 W.3
# 1 b 1 14 6 8 Y K M
# 2 b 2 14 5 11 F A P
# 3 c 3 13 8 14 Q J M
# 4 e 4 13 6 7 D W E
# 5 b 5 10 8 12 G I V
Die „halblange“ Ausgabe, die ich suche.Leicht zu erreichen mit Basis-Rs reshape.
reshape(myDf, direction = "long", idvar=1:2, varying = 3:ncol(myDf))
# ID.1 ID.2 time V W
# b.1.1 b 1 1 14 Y
# b.2.1 b 2 1 14 F
# c.3.1 c 3 1 13 Q
# e.4.1 e 4 1 13 D
# b.5.1 b 5 1 10 G
# b.1.2 b 1 2 6 K
# b.2.2 b 2 2 5 A
# c.3.2 c 3 2 8 J
# e.4.2 e 4 2 6 W
# b.5.2 b 5 2 8 I
# b.1.3 b 1 3 8 M
# b.2.3 b 2 3 11 P
# c.3.3 c 3 3 14 M
# e.4.3 e 4 3 7 E
# b.5.3 b 5 3 12 V
melt ist großartig, wenn Sie das Äquivalent von wollen stack, besonders seit stack verwirft alles factor Variablen, was frustrierend ist, wenn read.table und Familie ist standardmäßig auf stringsAsFactors = TRUE.(Sie können dafür sorgen, dass es funktioniert, aber Sie müssen die entsprechenden Spalten konvertieren character bevor Sie es verwenden können stack).Aber es ist nicht das, wonach ich suche, insbesondere aufgrund der Art und Weise, wie es mit der Spalte „Variable“ umgegangen ist.
library(reshape2)
myDfL <- melt(myDf, id.vars=1:2)
head(myDfL)
# ID.1 ID.2 variable value
# 1 b 1 V.1 14
# 2 b 2 V.1 14
# 3 c 3 V.1 13
# 4 e 4 V.1 13
# 5 b 5 V.1 10
# 6 b 1 V.2 6
Um dies zu beheben, muss man zunächst die Spalte „Variable“ aufteilen und dann verwenden dcast um das gleiche Ausgabeformat zu erhalten, das Sie erhalten würden reshape.
myDfL <- cbind(myDfL, colsplit(myDfL$variable, "\\.", names=c("var", "time")))
dcast(myDfL, ID.1 + ID.2 + time ~ var, value.var="value")
# ID.1 ID.2 time V W
# 1 b 1 1 14 Y
# 2 b 1 2 6 K
# 3 b 1 3 8 M
# 4 b 2 1 14 F
# 5 b 2 2 5 A
# 6 b 2 3 11 P
# 7 b 5 1 10 G
# 8 b 5 2 8 I
# 9 b 5 3 12 V
# 10 c 3 1 13 Q
# 11 c 3 2 8 J
# 12 c 3 3 14 M
# 13 e 4 1 13 D
# 14 e 4 2 6 W
# 15 e 4 3 7 E
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