R中时间序列图的传说

Question

我如何在下面的情节中添加传说？

library(quantmod)
library(PerformanceAnalytics)
library(imputeTS)
library(PortfolioAnalytics)

tickers <- c("FB", "AAPL", "AMZN", "NFLX")
weights <- c(.25, .25, .25, .25)

portfolioPrices <- NULL
for (Ticker in tickers)
  portfolioPrices <- cbind(portfolioPrices,
                           getSymbols.yahoo(Ticker, from="2016-01-01", periodicity = "daily", auto.assign=FALSE)[,4])

plot(portfolioPrices, legend = tickers)

Answer 1

如果将portfolioPrices转换为dataframe，然后分别添加每一行，则可以添加一个图例。

下面的代码没有创建最好看的情节/图例，但您可以通过使用图例/绘图参数来改进它。

此外，可以使用循环而不是硬编码来添加行。

library(quantmod)
library(PerformanceAnalytics)
library(imputeTS)
library(PortfolioAnalytics)

tickers <- c("FB", "AAPL", "AMZN", "NFLX")
weights <- c(.25, .25, .25, .25)

portfolioPrices <- NULL
for (Ticker in tickers)
  portfolioPrices <- cbind(
    portfolioPrices,
    getSymbols.yahoo(
      Ticker,
      from = "2016-01-01",
      periodicity = "daily",
      auto.assign = FALSE
    )[, 4]
  )
portfolioPrices <- data.frame(portfolioPrices)


plot(
  x = as.Date(rownames(portfolioPrices)),
  portfolioPrices$FB.Close,
  col = "black",
  type = "l",
  ylim = c(min(portfolioPrices), max(portfolioPrices)),
  main = "Stocks",
  xlab = "Date",
  ylab = "Price"
)
lines(x = as.Date(rownames(portfolioPrices)),
      portfolioPrices$AAPL.Close,
      col = "blue")
lines(x = as.Date(rownames(portfolioPrices)),
      portfolioPrices$AMZN.Close,
      col = "green")
lines(x = as.Date(rownames(portfolioPrices)),
      portfolioPrices$NFLX.Close,
      col = "red")

legend(
  "topleft",
  legend = tickers,
  col = c("black", "blue", "green", "red"),
  cex = 0.5,
  lwd = 2
)

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