Plotly in R: How to reference and extract figure values? - r

Question

I want to know how can I access, extract, and reference values from a plotly figure in R.
Consider, for example, the Sankey diagram from plotly's own site of which there is an abbreviated version here:
library(plotly)
fig <- plot_ly(
type = "sankey",
node = list(
label = c("A1", "A2", "B1", "B2", "C1", "C2"),
color = c("blue", "blue", "blue", "blue", "blue", "blue"),
line = list()
),
link = list(
source = c(0,1,0,2,3,3),
target = c(2,3,3,4,4,5),
value = c(8,4,2,8,4,2)
)
)
fig
If I do View(fig) in Rstudio, a new tab opens titled . (I don't know why this instead of 'fig'). In this tab I can go to x > visdat > 'strig of letters and numbers that is a function?' > attrs > node > x (as shown bellow).
Here all the x coordinates for the Sankey nodes appear.
I want to access these values so I can use them somewhere else. How do I do this? If I click on the right side of the Rsutudio tab to copy the code to console I get:
environment(.[["x"]][["visdat"]][["484c3ec36899"]])[["attrs"]][["node"]][["x"]]
which obviously doesn't work as there is no object named ..
In this case I have tried fig$x$visdat$`484c3ec36899`() but I cant do fig$x$visdat$`484c3ec36899`()$attr, and I don't know what else to do.
So, how can I access any value from a plotly object? Any documentation referencing this topic would also be helpful.
Thanks.

Answer 1

You can find the documentation of the data structure of plotly in R here: https://plotly.com/r/figure-structure/
To check the data structure you can use str(fig):
List of 8
$ x :List of 6
..$ visdat :List of 1
.. ..$ a3b8795a4:function ()
..$ cur_data: chr "a3b8795a4"
..$ attrs :List of 1
.. ..$ a3b8795a4:List of 6
.. .. ..$ node :List of 3
.. .. .. ..$ label: chr [1:6] "A1" "A2" "B1" "B2" ...
.. .. .. ..$ color: chr [1:6] "blue" "blue" "blue" "blue" ...
.. .. .. ..$ line : list()
.. .. ..$ link :List of 3
.. .. .. ..$ source: num [1:6] 0 1 0 2 3 3
.. .. .. ..$ target: num [1:6] 2 3 3 4 4 5
.. .. .. ..$ value : num [1:6] 8 4 2 8 4 2
.. .. ..$ alpha_stroke: num 1
.. .. ..$ sizes : num [1:2] 10 100
.. .. ..$ spans : num [1:2] 1 20
.. .. ..$ type : chr "sankey"
..$ layout :List of 3
.. ..$ width : NULL
.. ..$ height: NULL
.. ..$ margin:List of 4
.. .. ..$ b: num 40
.. .. ..$ l: num 60
.. .. ..$ t: num 25
.. .. ..$ r: num 10
..$ source : chr "A"
..$ config :List of 1
.. ..$ showSendToCloud: logi FALSE
..- attr(*, "TOJSON_FUNC")=function (x, ...)
$ width : NULL
$ height : NULL
$ sizingPolicy :List of 6
..$ defaultWidth : chr "100%"
..$ defaultHeight: num 400
..$ padding : NULL
..$ viewer :List of 6
.. ..$ defaultWidth : NULL
.. ..$ defaultHeight: NULL
.. ..$ padding : NULL
.. ..$ fill : logi TRUE
.. ..$ suppress : logi FALSE
.. ..$ paneHeight : NULL
..$ browser :List of 5
.. ..$ defaultWidth : NULL
.. ..$ defaultHeight: NULL
.. ..$ padding : NULL
.. ..$ fill : logi TRUE
.. ..$ external : logi FALSE
..$ knitr :List of 3
.. ..$ defaultWidth : NULL
.. ..$ defaultHeight: NULL
.. ..$ figure : logi TRUE
$ dependencies :List of 5
..$ :List of 10
.. ..$ name : chr "typedarray"
.. ..$ version : chr "0.1"
.. ..$ src :List of 1
.. .. ..$ file: chr "htmlwidgets/lib/typedarray"
.. ..$ meta : NULL
.. ..$ script : chr "typedarray.min.js"
.. ..$ stylesheet: NULL
.. ..$ head : NULL
.. ..$ attachment: NULL
.. ..$ package : chr "plotly"
.. ..$ all_files : logi FALSE
.. ..- attr(*, "class")= chr "html_dependency"
..$ :List of 10
.. ..$ name : chr "jquery"
.. ..$ version : chr "1.11.3"
.. ..$ src :List of 1
.. .. ..$ file: chr "lib/jquery"
.. ..$ meta : NULL
.. ..$ script : chr "jquery.min.js"
.. ..$ stylesheet: NULL
.. ..$ head : NULL
.. ..$ attachment: NULL
.. ..$ package : chr "crosstalk"
.. ..$ all_files : logi TRUE
.. ..- attr(*, "class")= chr "html_dependency"
..$ :List of 10
.. ..$ name : chr "crosstalk"
.. ..$ version : chr "1.1.0.1"
.. ..$ src :List of 1
.. .. ..$ file: chr "www"
.. ..$ meta : NULL
.. ..$ script : chr "js/crosstalk.min.js"
.. ..$ stylesheet: chr "css/crosstalk.css"
.. ..$ head : NULL
.. ..$ attachment: NULL
.. ..$ package : chr "crosstalk"
.. ..$ all_files : logi TRUE
.. ..- attr(*, "class")= chr "html_dependency"
..$ :List of 10
.. ..$ name : chr "plotly-htmlwidgets-css"
.. ..$ version : chr "1.52.2"
.. ..$ src :List of 1
.. .. ..$ file: chr "htmlwidgets/lib/plotlyjs"
.. ..$ meta : NULL
.. ..$ script : NULL
.. ..$ stylesheet: chr "plotly-htmlwidgets.css"
.. ..$ head : NULL
.. ..$ attachment: NULL
.. ..$ package : chr "plotly"
.. ..$ all_files : logi FALSE
.. ..- attr(*, "class")= chr "html_dependency"
..$ :List of 10
.. ..$ name : chr "plotly-main"
.. ..$ version : chr "1.52.2"
.. ..$ src :List of 1
.. .. ..$ file: chr "htmlwidgets/lib/plotlyjs"
.. ..$ meta : NULL
.. ..$ script : chr "plotly-latest.min.js"
.. ..$ stylesheet: NULL
.. ..$ head : NULL
.. ..$ attachment: NULL
.. ..$ package : chr "plotly"
.. ..$ all_files : logi FALSE
.. ..- attr(*, "class")= chr "html_dependency"
$ elementId : NULL
$ preRenderHook:function (p, registerFrames = TRUE)
$ jsHooks : list()
- attr(*, "class")= chr [1:2] "plotly" "htmlwidget"
- attr(*, "package")= chr "plotly"
You could extract the coordinates with:
unlist(fig$x$attrs)