> > ts <- ts(data$QtyPerWeek, frequency=52) > > HoltWinters(ts,0.46924,0.05,0.2) > > > > This results in the following error. "Error in decompose(ts(x[1L:wind], > > start = start(x), > frequency = f), seasonal) : time series has no or less than 2 periods"
Since you have set the frequency of the time series to 52, you need to have 104 observations to get the initial estimate of the seasonal pattern. How many observations are in 'ts'? If you don't have enough you can omit the seaonal component (HoltWinters(gamma=FALSE,...)), change start.periods from the default 2 to 1, or supply a 52-long vector of the initial seasonal pattern as the s.start argument. If you do have more than 104 observations then you will have to tell us more about the data. Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of David Winsemius > Sent: Thursday, October 03, 2013 12:39 PM > To: Daniel Hickman > Cc: r-help@r-project.org > Subject: Re: [R] time series has no or less than 2 periods > > > On Oct 3, 2013, at 8:32 AM, Daniel Hickman wrote: > > > Hello, > > > > > > > > I have been tasked with taking an excel file that my colleague had > > implemented Triple > Exponential Smoothing and recreate using R. > > > > The following image shows the before and after of smoothing out a fixed > > interval time > series data using Triple Exponential Smoothing inside of Excel. > > > > enter image description here > > The image file formats that I know are acceptable are .ps, .pdf or .png. Not > sure about > jpeg. > > > > > I am trying to perform the same triple exponential smoothing in R. I > > created a csv file > with the before smoothing data. The csv file is attached and can also be > found here. > > Need to send with .txt extension. > > > > > I found the HoltWinters method but I keep getting an error when I try to > > apply > HoltWinters against the csv. > > setwd("C:/temp") > > data <- read.table("TripleExpSmoothingXLS.csv", header=TRUE, sep=",") > > ts <- ts(data$QtyPerWeek, frequency=52) > > HoltWinters(ts,0.46924,0.05,0.2) > > > > This results in the following error. "Error in decompose(ts(x[1L:wind], > > start = start(x), > frequency = f), seasonal) : time series has no or less than 2 periods" > > Perhaps a data entry problem. We would need to see either the file or output > of > str(data). > > > > In case it helps, excel file with the triple exponential smoothing > > formulas and original > data can be found here. > > Again.... there is no here here. > > > > > Any advice? > > > > Thanks, Dan______________________________________________ > > R-help@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > David Winsemius > Alameda, CA, USA > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
