如何将指标动态添加到 quantmod 图表

Question

我想向 quantmod 图表动态添加指标。我可以成功添加 1 个指标，但如何添加多个存储在字符向量中的指标？

#### THIS WORKS
VariableTA = "addBBands()"
df<-data.frame (Open = seq(2,102,1), High = seq(6,106,1), Low = seq(3,103,1), Close = seq(4,104,1))
date = as.POSIXct(seq(as.Date("2015-01-01"), as.Date("2015-06-04"), by="days")[1:101])
dat<-as.xts(df, tzone = Sys.getenv("GMT"), order.by =as.POSIXct(as.character(date)))
chartSeries(dat )
eval(parse(text = VariableTA))

#NOW I HAVE 2 indicator and it does not work
VariableTA = c("addBBands()","addEMA()")
df<-data.frame (Open = seq(2,102,1), High = seq(6,106,1), Low = seq(3,103,1), Close = seq(4,104,1))
date = as.POSIXct(seq(as.Date("2015-01-01"), as.Date("2015-06-04"), by="days")[1:101])
dat<-as.xts(df, tzone = Sys.getenv("GMT"), order.by =as.POSIXct(as.character(date)))
chartSeries(dat )
for(i in 1: length(VariableTA))
{
  eval(parse(text = VariableTA[i]))
}

Answer 1

如果您只需通过 TA= 参数指定它们会容易得多 chartSeries。

require(quantmod)
data(sample_matrix)
x <- as.xts(sample_matrix)
VariableTA = "addBBands();addEMA()"
chartSeries(x, TA=VariableTA)