#Methuselah Walk Tree Ring Data collected by Donald A Graybill 

loc=file.path("ftp://ftp.ncdc.noaa.gov/pub/data/paleo/treering/chronologies/northamerica/usa/ca535.crn")
	test=download.file(loc,"temp.dat")  
	fred=readLines("temp.dat")

z<-seq(4,length(fred));
x<-fred[z]; # skip 3-line header

decades<-na.omit(as.numeric(substr(x,7,10)));range(decades);

cols2 <- cumsum(c(14,rep(7,9)))
cols1 <- cumsum(c(11,rep(7,9)))
cols  <- cbind(cols1,cols2)

X <- array(NA, dim=c(length(x),10)); #initialise X
f=function(i){ f=substr(x,cols[i,1],cols[i,2]);f};  
for (i in 1:10) (X[,i]=f(i)); # extract chronology values
for(i in 1:10) for (j in 1:length(x)) {X[j,i]=as.numeric(X[j,i])};
temp <- (X==9990);X[temp]=NA; #replace 9990 with NA

count<-sum(apply(!is.na(X),1,sum));
start_year <- as.numeric(substr(x[1],6,10));
end <- start_year+count-1;
years <- start_year:end;
chronology <- years;
chronology <- data.frame(years);

chronology$values <- as.numeric(na.omit(as.vector(t(X))))

treeRing.ts <- ts(chronology$values, start = start_year, delta =1)
plot(treeRing.ts,main="Methuselah Walk Tree Ring Chronology", font.main=2,ylim=c(0,2000),ylab="Growth Index", xlab="Year",font.axis=2,font.lab=3)