R plot_ly() adding vertical lines to time data [duplicate] - r

Question

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Horizontal/Vertical Line in plotly
(4 answers)
Closed 2 years ago.
I would like to add a vertical line on a special date to my plot. I am using the plot_ly() function from the plotly package in R.
p <- plot_ly(dt.allDataFvsS, x = dt.allDataFvsS$date, y = dt.allDataFvsS$meanDifference, mode = 'lines',
type = "scatter", line = list(color = " #007d3c")) %>%
layout(title = "Average Price Difference Forward vs. Spot", xaxis = list(title = "Date"),
yaxis = list(title = "EUR / MWh"))
The date has the following form: e.g. "2018-10-01" ("Y-M-D")
My plot looks like this:
PLOT
So, my question is how do I get a black vertical line at date "2018-10-01" ?
Is it also possible to have vertical lines at the beginning of each year? Or of every quarter (Jan - Apr - Jul - Oct) of each year?
I would be very happy if someone could help me? Unfortunately, after a day of browsing the internet, I couldn't find anything that worked.

Answer 1

As no data is provided to reproduce your issue, I would suggest next approach using add_trace() function where you define the coordinates for the line:
p <- plot_ly(dt.allDataFvsS, x = dt.allDataFvsS$date, y = dt.allDataFvsS$meanDifference, mode = 'lines',
type = "scatter", line = list(color = " #007d3c")) %>%
add_trace(x =as.Date("2018-10-01"),type = 'scatter', mode = 'lines',
line = list(color = 'black'),name = '') %>%
layout(title = "Average Price Difference Forward vs. Spot", xaxis = list(title = "Date"),
yaxis = list(title = "EUR / MWh"))
Let me know if that works!

Answer 2

Here is another approach based on shapes rather than adding another trace (you can see the difference when zooming out + there is no legend item for the vertical line):
library(plotly)
dates <- seq(from = as.Date("2018-08-01"), to = as.Date("2018-12-31"), by = 1)
dt.allDataFvsS <- data.frame(date = dates, meanDifference = sin(seq_along(dates)*0.1))
vline <- function(x = 0, color = "red") {
list(
type = "line",
y0 = 0,
y1 = 1,
yref = "paper",
x0 = x,
x1 = x,
line = list(color = color)
)
}
p <- plot_ly(dt.allDataFvsS, x = dt.allDataFvsS$date, y = dt.allDataFvsS$meanDifference, mode = 'lines',
type = "scatter", line = list(color = " #007d3c")) %>%
layout(title = "Average Price Difference Forward vs. Spot", xaxis = list(title = "Date"),
yaxis = list(title = "EUR / MWh"))
p %>% layout(shapes = list(vline(as.Date("2018-10-01"))))
Based on this answer.