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我試圖在名爲Reference的數據框中插入一列,並從另一個稱爲Quotes的數據框中獲取股票的回報。從數據框插入返回
Quotes <- data.frame (Ticker = c("Petr4","Petr4","Petr4","Abev3","Abev3","Petr4","Petr4","Abev3","Abev3","Abev3"),
Close = c(15.80,15.55,15.90,18.52,19.57,16.25,16.50,19.20,19.18,19.7))
Reference <- aggregate(cbind(Close) ~ Ticker, data = (Quotes), FUN = last)
這是插入的列如何想(最後N天的返程):使用Quantmod FUN最後得到最後的報價,任何其他的想法
Reference$Return <- c(0.044303797,0.063714903)
I'm?
您能否更具體地說明c(0.044303797,0.063714903)如何從給定的數據框計算出來? – Kim