I am trying to replicate this example of a multiline chart with dots. My data is basically the same, where I have an object with name and values in the first level, and then a couple of values in the second level, inside values. The length of the arrays inside values is 40.
Now, one requirement is that all the dots for all the paths are inside the same g group within the DOM. This is giving me a lot of trouble because I can't seem to figure out how to join the circles with the appropriate portion of the nested data.
The last thing I've tried is this:
var symbolsb = d3.select("#plot-b") // plot-b is the graph area group within the svg
.append("g")
.attr("id", "symbols-b");
symbolsb.selectAll("circle")
.data(games, function(d) {console.log(d.values) // games is my data object
return d.values})
.enter()
.append("circle")
.attr("class", "symbolsb")
.attr("cx", function(d,i) {console.log(d)
return x(d.values.date);})
.attr("cy", function(d,i) {return y_count(d.count);})
.attr("r", function(d,i) {
let parent = this.parentNode;
let datum = d3.select(parent).datum();
console.log(parent)
if (i%3 === 1 && included_names.includes(datum[i].name)) {
return 8;}
else {return null;}})
.style("fill", function(d,i) {
let parent = this.parentNode;
let datum = d3.select(parent).datum();
{return color(datum.name);}});
As I (incorrectly) understand the data() function, I thought that by returning d.values, the functions in cx, cy, and r would just see the array(s) that is inside d.values, but when log d to the console within the functions to define cx, cy, etc. I see again the full object games. Again, I though I should only get the values portion of the object.
I have been able to get a plot that looks like the result I want by loading the data and appending a g when defining symbolsb, but this creates a group for each set of circles.
I think the problem comes from my confusion of how nested objects are accessed by the data() function. So any help explaining that would be greatly appreciated.
It would be great if you could provide a live reproduction, for example in an Observable or VizHub notebook.
This line looks suspect
.data(games, function(d) {console.log(d.values) // games is my data object
return d.values})
The second argument to *selection*.data should be a 'key function', a function that returns a unique string identifier for each datum. Here you are giving an object (d.values) which will get stringified to [object Object] for each data point. This also explains why you're seeing the full games object when logging. I think it's safe here to just remove the second argument to .data():
.data(games)
This also doesn't look right
.attr("r", function(d,i) {
let parent = this.parentNode;
let datum = d3.select(parent).datum();
console.log(parent)
if (i%3 === 1 && included_names.includes(datum[i].name)) {
return 8;}
else {
return null;
*emphasized text*}})
I'm not entirely sure what you're trying to do here. If you're trying to access the name of the data point you can just access it on the data point itself using .attr("r", function(d,i) { if (included_names.includes(d.name)) { return 8 } else { return 0} )