Create a <hr> between Plot markers?

Notebooks
1

Hi everyone! I have a categorical heatmap that I want to add a sort of line break to between two categories - I’ve tried using ruleY but to no avail… How would I make a black horizontal line between “param3” and “Collector Initials” in the following example: Combining heatmaps / Maya Gans | Observable

I combined the data but maybe I should really keep these as two separate vectors, then put some kind of spacer between?

I tried this:

    Plot.ruleY(["Collector Initials"], {
      stroke: 'black',
      strokeWidth: 2
    }),

but i essentially want be able to bump this line up/do a transform on it?

I also tried:

 y: {
    label: null,
    domain: [
  "param1", 
  "param2", 
  "param3", 
 "spacer",
  "Collector Initials",  
  "Time Collected"
];
  },

then put the like at “Spacer” but I dont want to see the word spacer or have an axis tick, and it was really thick (the same thickness as other y-axis marks) so i dont love that…

Any thoughts appreciated!!

2

I’m afraid this is not supported in Plot (and not even in D3 scales). It would be useful though! A new type of ordinal scale that has a tree as domain rather than a list. Note that a similar question was asked in Grid within plot.cell