Monthly Sunspot Data, 1749–1997

Description

Monthly numbers of sunspots.

Usage

sunspot.month

Format

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

Note

Prior to R 2.0.0 sunspot.month and sunspot.year were copied to the user's workspace (or elsewhere) by data(sunspot). However, as package lattice has a dataset sunspot which can be retrieved by the same command, that usage has been removed.

Source

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

See Also

sunspot.month is a longer version of sunspots that runs until 1988 rather than 1983.

Examples

require(stats)
## Compare the monthly series 
plot (sunspot.month, main = "sunspot.month [stats]", 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))