require(dplR)
data(co021)
series <- co021[, 1]
series <- series[!is.na(series)]
png("Z:/huxley/prod/treering/images/splines.png",480,360,bg="transparent")
par(tcl = 0.5, mgp = c(1.25, 0.25, 0),xaxs="i")
plot(series, type = "n", ylab = "Ring Width (mm)", xlab="Tree Age",
     main="Splines")
grid(lty=1,col="black")
axis(1);axis(2);axis(3);axis(4)
lines(series,col="grey10")
lines(ffcsaps(series, nyrs = 16), col = "red", lwd = 2)
lines(ffcsaps(series, nyrs = 64), col = "green", lwd = 2)
## nyrs defaults to 0.5*length(series) == 347
lines(ffcsaps(series), col = "blue", lwd = 2)
legend("topright",
       c("Series", "nyrs=16", "nyrs=64",
         paste("Default nyrs (", length(series) / 2, ")", sep="")),
       fill=c("grey10", "red", "green", "blue"),bg="grey90")
dev.off()