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rplotlyopacity

R plto_ly or ggplot: fade in line with changing opacity

In an plot_ly plot I want a line to fade in using the opacity parameter. I thought I group the data into as many groups as there are datapoints and add an opacity parameter. However the groups do not get connected so there is nothing plotted.

library(plotly)
xg = as.character(c(1:100))  
df <- data.frame(x = 1:100,xg = as.factor(xg), y = 1:100, opacity =0.01*(1:100))

df <-group_by(df, xg)
plot_ly(df)%>%
add_trace( x =~x, y= ~y, opacity = ~opacity )

And it doesent even work with markers, the opacity is constant:

library(plotly)
xg = as.character(c(1:100))  
df <- data.frame(x = 1:100,xg = as.factor(xg), y = 1:100, opacity =0.01*(1:100))

df <-group_by(df, xg)
plot_ly(df)%>%
add_markers( x =~x, y= ~y, opacity = ~opacity )
Solution

  • I think this is what you're looking for, but correct me if I'm wrong. Here I'll make the plot in ggplot, then covert to plotly.

    library(ggplot2)
library(plotly)
p <- ggplot(df,aes(x =x, y = y,alpha = opacity))+
    geom_point()+
    theme_classic()

ggplotly(p)

    enter image description here

    I think what you're looking for to "fade" the line is the alpha argument.