Vega-lite chart horizontal rule "jumps" with some datasets but not others

Question

I'm trying to build what I think should be simple functionality using vega-Lite, but I'm struggling to get it working.

So I basically have a simple line chart plotting values on the y axis and frequency on the x axis. So far so good, no problem.

Now what I want is a vertical rule I can use to select an arbitrary point (frequency) on the X axis with the mouse. The rule should follow this point.

I actually have this working, however, on some datasets the rule sort of "jumps" on the axis, making it so that not all frequencies are selectable. You can see a Gist with one of the problematic specs here: https://gist.github.com/mkoelbaek-skyspecs/cbb49c75db743a4179a82b8a48f8c2da . Try showing it in vega-editor and dragging the selection rule and you'll see that it "jumps" and some points are not actually selectable. (Couldn't like to vega-editor directly since the url-encod with the dataset was to large for Stack Overflow).

What am I doing wrong?

Thank you in advance

Answer 1

So it turns out vegas "nearest" functionality got confused due to the sheer amount of data points I had. (I guess it's beta still).

I ended up creating a new field on my dataset called "SelectionX" which was still frequency, but locked to n discrete steps (400 in my case). Then SelectionX is what I'm using to set my rule parameter, and it works!.