sunspot                  package:ts                  R Documentation

Yearly Sunspot Data, 1700-1988.
Monthly Sunspot Data, 1749-1997.

Description:

     Monthly and yearly number of sunspots.

Usage:

     data(sunspot)

Format:

     The univariate time series `sunspot.year' and `sunspot.month'
     contain 289 and 2988 observations, respectively. The objects are
     of class `"ts"'.

Source:

     Monthly data: Sunspot Index Data Center, World Data Center-C1 For
     Sunspot Index Royal Observatory of Belgium, Av. Circulaire, 3,
     B-1180 BRUSSELS <URL:
     http://www.oma.be/KSB-ORB/SIDC/sidc_txt.html>

     Yearly data: H. Tong (1996) Non-Linear Time Series. Clarendon
     Press, Oxford, p. 471.

See Also:

     `sunspot.month' is a longer version of `sunspots' in base R, that
     runs until 1988.

Examples:

     ## Compare the monthly series from 'base' and 'ts':
     data(sunspots, package = base)
     data(sunspot,  package = ts)
     plot (sunspot.month, main = "sunspot.month [ts]", col = 2)
     lines(sunspots)# ``very barely'' see something

     ## Now look at the difference :
     all(tsp(sunspots)     [c(1,3)] ==
         tsp(sunspot.month)[c(1,3)]) ## Start & Periodicity are the same
     n1 <- length(sunspots)
     table(eq <- sunspots == sunspot.month[1:n1]) #>  132  are different !
     i <- which(!eq) 
     rug(time(eq)[i])
     s1 <- sunspots[i] ; s2 <- sunspot.month[i]
     cbind(i = i, sunspots = s1, ss.month = s2,
           perc.diff = round(100*2*abs(s1-s2)/(s1+s2), 1))

