How to plot time series for stock data using R

Question

We have a dataset which has open,high,low and close values. We have normalized the data and trying to plot normalized open values against Date.

The dataset can be found at http://finance.yahoo.com/quote/ORCL/history?period1=1323475200&period2=1481328000&interval=1d&filter=history&frequency=1d

We tried to replicate the graphs from https://stats.stackexchange.com/questions/39279/how-to-plot-20-years-of-daily-data-in-time-series

The output is not as expected.

Code:

oracle$date <- as.Date(oracle$Date,"%y-%m-%d")
print(oracle$date)

Issue 1: It prints dates up to 2027 even when have values from 2011-2016.

oracle$week <-(as.integer(oracle$date) + 3) %/% 7
print (oracle$week)
oracle$week <- as.Date(oracle$week * 7 - 3, as.Date("2011-12-12", "%Y-%m-%d"))
print(oracle$week)
par(mfrow=c(1,2))
plot(as.factor(unclass(oracle$Date[1:1259])), oracle$NO[1:1259], type="l",
     main="Original Plot: Inset", xlab="Factor code")
plot(oracle$Date[1:1259], oracle$NO[1:1259], type="n", ylab="Price", 
     main="Oracle Opening Prices")

Graphs are not displayed as shown in answer (8) of https://stats.stackexchange.com/questions/39279/how-to-plot-20-years-of-daily-data-in-time-series

It is as displayed below:

tmp <- by(oracle[1:1259,], oracle$week[1:1259], function(x) lines(x$Date, x$NO, lwd=2))
print(tmp)
par(mfrow=c(1,1))
colors <- terrain.colors(52)
plot(oracle$Date, oracle$NO, type="n", main="Oracle Opening Prices")
tmp <- by(oracle, oracle$week, 
function(x) lines(x$date, x$Open, col=colors[x$week %% 52 + 1]))
print(tmp)

Answer 1

This is commonly done in R using the Quantmod package and getSymbols wrapper. A good built-in chart setup is from the PerformanceAnalytics package.

require(quantmod)
require(PerformanceAnalytics)
getSymbols("ORCL", from = "1996-01-01")
chart.TimeSeries(ORCL[,1], main = "Oracle Opening Prices")

However, since I am not entirely sure what answer (8) mean (the one with 8 upvotes?), I cannot determine exactly what plot you want.