Adding hover tooltip for "NaN" values in choropleth

How do I add hover tooltips for values that are “NaN” in choropleths? Is there a way to change the color of “NaN” states to gray?

See https://codepen.io/etpinard/pen/ExYerMx?editors=1010

We don’t render locations with NaN values and in turn that they don’t get hover labels.


I would suggest splitting your data arrays into two traces, one with non-NaNs values and one showing the NaN using some dummy value: https://codepen.io/etpinard/pen/mdbGvYM?editors=1010