Add vertical lines to quantmod::chart_Series

Question

I want to add vertical lines on several dates on a certain graph. So far I haven\'t managed to achieve this simple task. This is what I tried:

> s <-          


        

Answer 1

add horizontal line my example:

library(quantmod)
library(lubridate)

stockId<-"CVS"
showperiod<-6   # 6 months

stockData<-getSymbols(stockId, src="yahoo",auto.assign=FALSE)

startDate<-Sys.Date()-months(showperiod,abbreviate = FALSE)
fromDate<-paste0(year(startDate),month(startDate))

subset<-paste0(fromDate,"/")

mytheme <- chart_theme() 
mytheme$col$dn.col  <- "firebrick1" 
mytheme$col$up.col  <- "darkgreen"
chart_Series(stockData, name = stockId, subset = subset, theme = mytheme)

#if you add line at 2018-6-18 to 2018-07-16 & y(price)=72
#you need creat new data to plot
#
ntick<-nrow(stockData["20180618/20180716"]) #2018-6-18 to 2018-07-16 tick numbers
getDate<-index(stockData["20180618/20180716"])
y<-rep(72,ntick)
df<-data.frame(getDate,y)
linedata<-xts(df$y,order.by = df$getDate)
# add line
add_TA(linedata,on=-1,col="blue",lwd=2)

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