Candlestick plots are something you see regularly when dealing with stocks. Whether you are an investor, an analyst or even an outsider, this type of chart always in interesting to look at. In this brief blog, I’m going to share a custom function I made for making a candlestick charts using ggplot2 and the tidyquant packages.

Sure tidyquant has their own charting function chart_Series(), but I wanted to create my own and give it a shot. I really like how it turned out aesthetically, if you think the same- feel free to use it!

The code

The code here is pretty straight forward. It utilizes the yahooFinance api request function made by tidyquant and pipes it directly into home-made ggplot2 candlestick plot.

# Libraries we need
library(tidyverse)
library(tidyquant)
# Configuring settings as per tidyquant tutorial
options("getSymbols.warning4.0"=FALSE)
options("getSymbols.yahoo.warning"=FALSE)

# The function
candleStick_plot<-function(symbol,from,to){
  tq_get(symbol,
        from = from,
        to = to,
        warnings = FALSE) %>% 
    mutate(greenRed=ifelse(open-close>0,
                           "Red",
                           "Green")) %>% 
    ggplot()+
    geom_segment(aes(x = date,
                     xend=date,
                     y =open,
                     yend =close,
                     colour=greenRed),
                 size=3)+
    theme_tq()+
    geom_segment(aes(x = date,
                     xend=date,
                     y =high,
                     yend =low,
                     colour=greenRed))+
    scale_color_manual(values=c("Forest Green","Red"))+
    ggtitle(paste0(symbol," (",from," - ",to,")"))+
    theme(legend.position ="none",
          axis.title.y = element_blank(),
          axis.title.x=element_blank(),
          axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1),
          plot.title= element_text(hjust=0.5))
}

Just copy the above code and have a blast!

Testing it out

# Bitcoin Price
# Time of writing this blog 9/14/2021
candleStick_plot("BTC-USD",from = '2021-07-01',to = lubridate::today())

# Bombardier Price
# Time of writing this blog 9/14/2021
candleStick_plot('BBD-B.TO',from = '2021-07-01',to = lubridate::today())