Question

我正在尝试基于数据框中的一行生成包含动物每周遭遇历史的新数据框，该数据框包含动物ID（BandNo）我们跟踪它的第一天和最后一天（FDay，Lday），以及当我们停止跟踪它（命运）以及其他协变量时，动物的命运。

这是一个个体的示例数据框，对象“a”

structure(list(BandNo = structure(1L, .Label = c("1234", "4201", 
"4203", "4205", "4207", "4208", "4209", "4213", "4214", "4215", 
"4216", "4217", "4219", "4221", "4223", "4224", "4226", "4227", 
"4228", "4229", "4230", "4231", "4232", "4233", "4234", "4236", 
"4237", "4238", "4239", "4241", "4242", "4245", "4247", "4248", 
"4249", "4253", "4254", "4256", "4257", "4258", "4259", "4261", 
"4262", "4263", "4264", "4271", "4272", "4273", "4276", "4277", 
"4280", "4282", "4284", "4288", "4289", "4292", "4293", "4296", 
"4298", "4299", "4501", "4502", "4503", "4504", "4505", "4507", 
"4508", "4509", "4510", "4511", "4512", "4513", "4514", "4515", 
"4516", "4517", "4518", "4519", "4520", "4521", "4525", "4526", 
"4527", "4529", "4530", "4532", "4535", "4539", "4596", "4598", 
"4599", "6101", "6102", "6104", "6105", "6106", "6107", "6108", 
"6109", "6111", "6112", "6113", "6114", "6115", "6116", "6118", 
"6119", "8002", "8003", "8004", "8005", "8006", "8007", "8008", 
"8009", "8010", "8011", "8012", "8013", "8014", "8015", "8017", 
"8018", "8019", "8020", "8021", "8097", "8098", "8099", "8402", 
"8403", "8404", "8405", "8406", "8408", "8409", "8410", "8411", 
"8412", "8413", "8414", "8416", "8417", "8418", "8419", "8422", 
"8423", "8426", "8427", "8429", "8430", "8431", "8432", "8433", 
"8458", "8497", "8498"), class = "factor"), FDay = structure(1380171600, class = c("POSIXct", 
"POSIXt"), tzone = "America/Bogota"), Lday = structure(1392094800, class = c("POSIXct", 
"POSIXt"), tzone = "America/Bogota"), ObsLength = 138, Fate = "Predation", 
    FieldName = structure(7L, .Label = c("Bryan", "Dassow", "H1", 
    "H2", "NARD", "SAY160", "SAY320", "SAY40A", "Schaeffer", 
    "SIB", "Wessels"), class = "factor"), Landscape = structure(2L, .Label = c("CHW", 
    "SAY", "SIB"), class = "factor"), Sex = structure(1L, .Label = c("F", 
    "M"), class = "factor")), .Names = c("BandNo", "FDay", "Lday", 
"ObsLength", "Fate", "FieldName", "Landscape", "Sex"), row.names = 1L, class = "data.frame")

我可以使用以下代码成功创建我想要的新数据框：

library(lubridate)
mydate<-seq(from=a$FDay,to=a$Lday,by='week')
newband<-rep(a$BandNo,length(mydate))
newfate<-rep("Survive",length(mydate))
newfate[length(mydate)]<-a$Fate
y<-data.frame(newband,mydate,newfate)
y$FieldName<-a$FieldName
y$Sex<-a$Sex
y$Landscape<-a$Landscape
y$WeekID<-week(a$mydate)
y$Year<-year(a$mydate))

但是当我尝试使用以下代码将其应用于一行数据帧列表时，我收到错误消息“不知道如何将x转换为类POSIXlt”

之前的步骤，现在在lapply中使用，给出错误

b<-list(a)
d<-lapply(b,function(x){
mydate<-seq(from=x$FDay,to=x$Lday,by='week')
newband<-rep(x$BandNo,length(mydate))
newfate<-rep("Survive",length(mydate))
newfate[length(mydate)]<-x$Fate
y<-data.frame(newband,mydate,newfate)
y$FieldName<-x$FieldName
y$Sex<-x$Sex
y$Landscape<-x$Landscape
y$WeekID<-week(x$mydate)
y$Year<-year(x$mydate)})

感谢您的帮助！

Answer 1

我犯了一个真正的傻瓜错误......我本应该在最后引用y $ mydate。这是lapply函数应该是什么样的：

d<-lapply(adult2,function(x){
mydate<-seq(from=x$FDay,to=x$Lday,by='week')
newband<-rep(x$BandNo,length(mydate))
newfate<-rep("Survive",length(mydate))
newfate[length(mydate)]<-x$Fate
y<-data.frame(newband,mydate,newfate)
y$FieldName<-x$FieldName
y$Sex<-x$Sex
y$Landscape<-x$Landscape
y$WeekID<-week(y$mydate)
y$Year<-year(y$mydate)
return(y)}
)

在lapply中生成和填充新的数据框 - “不知道如何将x转换为类POSIXlt”

1 个答案: