D3 transition looping throwing Uncaught TypeError: t.call is not a function

Question

Very new to D3 and relatively new to JS in general. I am trying to create a circle on click, and that circle once created needs to repeatedly pulsate forever. Right now, it

Answer 1

This is because you are using d3 version4. There has been a major change in the v4 API, so:

Instead of using

// ...   
.each("end", pulsate);//in d3 version 3

do

// ...   
.on("end", pulsate);//in d3 version 4

refer: https://github.com/d3/d3-transition#transition_on