我是ts()，zoo()和zooreg()的新手。我正在处理每日时间序列数据，并且难以在zooreg和ts对象之间切换。具体来说，我想拟合一个模型来预测未来7天。
尝试下面的＃3似乎有效，但有没有比使用coredata更好的方法？另外，我已经阅读了ts()对象中每日数据的频率是365还是7的矛盾建议。尝试＃1和＃2显示我的尝试失败。
提前致谢。
罗布
#===================================
# load libraries
#===================================
require(zoo)
require(fpp)
#===================================
# create dummy dataset
#===================================
Lines <-
"2013-02-08 686160160
2013-02-09 765196250
2013-02-10 0
2013-02-11 0
2013-02-12 1208385570
2013-02-13 817502700
2013-02-14 640140270
2013-02-15 616020930
2013-02-16 735370160
2013-02-17 0
2013-02-18 0
2013-02-19 0
2013-02-20 1503211500
2013-02-21 831274360
2013-02-22 627096330
2013-02-23 721884800
2013-02-24 721884800
2013-02-25 0
2013-02-26 1169370020
2013-02-27 804955410
2013-02-28 628113780
2013-03-01 654291400
2013-03-02 815497620
2013-03-03 0
2013-03-04 0
2013-03-05 1406186740
2013-03-06 992812660
2013-03-07 768179720
2013-03-08 712639690
2013-03-09 795140640
2013-03-10 0
2013-03-11 0
2013-03-12 1230958890
2013-03-13 851839940
2013-03-14 667805530
2013-03-15 0
2013-03-16 1383085620
2013-03-17 0
2013-03-18 0
2013-03-19 1181950630
2013-03-20 828667350
2013-03-21 637237160
2013-03-22 615793920
"
#===================================
# read data in as zoo object
#===================================
a.zoo <- read.zoo(textConnection(Lines),
col.names = c("dates", "counts"),
colClasses = c("character", "numeric"),
index = 1, format = "%Y-%m-%d")
#===================================
# attempt #1
#===================================
length(a.zoo) # length is 43
a.ts <- as.ts(a.zoo) # convert to ts object
length(a.ts) # length is 43
# decompose a time series into seasonal, trend and irregular components using loess
frequency(a.ts) # frequency is 1
stl(a.ts, s.window=7) # gives error saying frequency < 2
#===================================
# attempt #2
#===================================
# add frequency of 365 to represent daily data
b.zooreg <- zoo(a.zoo, frequency = 365)
frequency(b.zooreg) # frequency is 365
str(b.zooreg) # length is 43, frequency = 365
b.ts <- as.ts(b.zooreg) # convert to ts object
length(b.ts) # length is NA padded to 15331
#===================================
# attempt #3
#===================================
# seems like a hack but works
ts2 <- ts(coredata(a.zoo),frequency=7,start=start(a.zoo))
ts2 # shows correct frequency and length
# strange "Start = c(15744, 1)" though
stl(ts2, s.window=7) # seems to work
plot(forecast(ts2))