Warbling circle using d3 - d3.js

I wanted to draw a pulsating warbling circle on a geomap using d3, using this example for guidance. However—and I know this is a very basic question, so apologies—I can't seem to get the selector to fire right. Here is the relevant code:
layer2
.attr("id", "locations")
.selectAll(".state")
.data(columbia.features)
.enter().append("circle")
.attr("class", "location")
.attr("r", "4px")
.attr("cx", function(d) { return proj(d['geometry']['coordinates'])[0]; })
.attr("cy", function(d) { return proj(d['geometry']['coordinates'])[1]; })
.attr("d", path)
.each(pulse);
function pulse() {
var circle = svg.select(".location");
console.log(circle);
(function repeat() {
circle = circle.transition()
.duration(2000)
.attr("stroke-width", 20)
.attr("r", 10)
.transition()
.duration(2000)
.attr('stroke-width', 0.5)
.attr("r", 200)
.ease('sine')
.each("end", repeat);
})();
}
Right now I have:
var circle = svg.select(".location");
What should I have instead of .location?
Here is the full file.
Edit: got it; I need selectAll, notselect.

Related

Trouble with storing enter selections containing transitions

If I try to store the following enter selection, I get an error when I try to access it. I don't have a problem if I remove the transition. Why? Are there other restrictions on storing selections? Here is an example:
// this works
var enterSel = d3.select("svg")
.selectAll("circle")
.data([100, 200, 300])
.enter()
.append("circle")
.attr("cx", d => d)
.attr("cy", "100")
.attr("fill", "red")
.attr("r", "0")
.transition()
.duration(2000)
.attr("r", "50");
The above appends and transitions three circles to red, as expected, but the enterSel variable cannot be used for further modifications:
// this doesn't work
enterSel.attr("fill", "green");
Uncaught Error: transition not found d3.v4.min.js:2
at zn (d3.v4.min.js:2)
at Cn (d3.v4.min.js:2)
at SVGCircleElement.<anonymous> (d3.v4.min.js:2)
at qn.each (d3.v4.min.js:2)
at qn.tween (d3.v4.min.js:2)
at qn.attrTween (d3.v4.min.js:2)
at qn.attr (d3.v4.min.js:2)
at <anonymous>:1:10
I can get around this by doing the transition separately, as follows, but I really want to understand why this is necessary.
// this works
var enterSel = d3.select("svg")
.selectAll("circle")
.data([100, 200, 300])
.enter()
.append("circle")
.attr("cx", d => d)
.attr("cy", "100")
.attr("fill", "red")
.attr("r", "0");
enterSel.transition()
.duration(2000)
.attr("r", "50");
enterSel.attr("fill", "green");
I'll post an answer for the future. A d3 selection returns a selection with the d3.selection.prototype. A transition on the other hand returns a transition with the d3.transition.prototype.
var enterSel = d3.select("svg")
.selectAll("circle")
.data([100, 200, 300])
.enter()
.append("circle")
.attr("cx", d => d)
.attr("cy", "100")
.attr("fill", "red")
.attr("r", "0")
.transition()
.duration(2000)
.attr("r", "50");
enterSel.attr("fill", "green");
Does not work because enterSel is now a transition and has different properties than a selection.
var enterSel = d3.select("svg")
.selectAll("circle")
.data([100, 200, 300])
.enter()
.append("circle")
.attr("cx", d => d)
.attr("cy", "100")
.attr("fill", "red")
.attr("r", "0");
enterSel.transition()
.duration(2000)
.attr("r", "50");
enterSel.attr("fill", "green");
This one works because enterSel is always a selection, which uses the selection prototype. The transition is sectioned away in the second call, but enterSel is always the selection of all the circles.
Hopefully this helps clear things up!

Transition effects in population pyramid

I am working on a population pyramid that has an updating function.
http://bricbracs.com/hh/
As you can see the bars expand and contract in a horizontal line when you update it with new data. I want to modify the transition effect so that the bars enter and exit vertically like this:
http://vis.stanford.edu/jheer/d3/pyramid/shift.html
I have been following this tutorial and modifying the code but so far no luck.
https://strongriley.github.io/d3/tutorial/bar-2.html
Here is the code that first draws the bars on loading. (this is the male bar group, the female bar group is the same)
leftBarGroup.selectAll('.bar.left')
.data(data)
.enter()
.append('rect')
.attr('class', 'bar left')
.attr('y', function(d) { return yScale(d.group); })
.attr("width", 0)
.attr("opacity", 0)
.transition()
.duration(500)
.attr('width', function(d) { return xScale(d.male); })
.attr('height', yScale.rangeBand())
.attr("opacity", 1)
And here is the corresponding part of the code in the updating function which changes the bars.
var sel = leftBarGroup.selectAll('.bar.left')
.attr('class', 'bar left')
.data(data)
.data(data, function(d) { return d.male; })
.transition()
.attr('y',0)
.duration(500)
.attr('y', function(d) { return yScale(d.group); })
.attr('height', yScale.rangeBand())
.attr('width', function(d) { return xScale(d.male); })
.attr('height', yScale.rangeBand())
Thanks in advance.
Here's one way to reproduce the effect in your linked example. I offset the bars and then slide them back into place. You then handle the top and bottom bars slightly different.
Note, I only did the slide down on the male side of the pyramid, if you need help going the rest of the way just leave me a comment.
var sel = leftBarGroup.selectAll('.bar.left')
.attr('class', 'bar left')
.data(data)
.data(data, function(d) {
return d.male;
})
// offset y to slide down
.attr('y', function(d){
var self = d3.select(this);
return +self.attr('y') - yScale.rangeBand();
})
.transition()
.duration(500)
// slide it back into place
.attr('y', function(d) {
return yScale(d.group);
})
// and set new width
.attr('width', function(d) {
return xScale(d.male);
});
// for the very top bar
// not only slide it but "fade it in"
leftBarGroup.select(':last-child')
.style('opacity', 0)
.transition()
.duration(500)
.style('opacity', 1)
.attr('y', function(d) {
return yScale(d.group);
});
// append a fake bar on the bottom
// to slide and fade out
leftBarGroup.append('rect')
.attr('y', function(d) {
return yScale('0-4');
})
.attr('height', yScale.rangeBand())
.attr('width', function(){
return leftBarGroup.select(':first-child').attr('width');
})
.style('fill', 'steelblue')
.style('opacity', 0.6)
.transition()
.duration(500)
.attr('y', function(d) {
return yScale('0-4') + yScale.rangeBand();
})
.style('opacity', 0)
.remove();
EDITS
Going up is just a matter of reversing the logic:
var sel = leftBarGroup.selectAll('.bar.left')
.attr('class', 'bar left')
.data(data)
.data(data, function(d) {
return d.male;
})
// offset y to slide up
.attr('y', function(d){
var self = d3.select(this);
return +self.attr('y') + yScale.rangeBand()
})
.transition()
.duration(500)
// slide it back into place
.attr('y', function(d) {
return yScale(d.group);
})
// and set new width
.attr('width', function(d) {
return xScale(d.male);
});
// for the very bottom bar
// not only slide it but "fade it in"
leftBarGroup.select(':first-child')
.style('opacity', 0)
.transition()
.duration(500)
.style('opacity', 1)
.attr('y', function(d) {
return yScale(d.group);
});
// append a fake bar on the top
// to slide and fade out
var w = leftBarGroup.select(':last-child').attr('width');
leftBarGroup.append('rect')
.attr('class','fake')
.attr('y', function(d) {
return yScale('90+');
})
.attr('height', yScale.rangeBand())
.attr('width', w)
.style('fill', 'steelblue')
.style('opacity', 0.6)
.transition()
.duration(500)
.attr('y', function(d) {
return yScale('90+') - yScale.rangeBand();
})
.style('opacity', 0)
.remove();
Updated code sample here.

Coordinates of each center's arc in a pie chart

In order to draw a baton that its starting point takes coordinates of arc's center in a Pie Chart d3 js, How can determinate coordinates of each arcs's center ?
I tried this code but only the first baton was in the right position.
var lines = arcs.selectAll("line")
.data(data)
.enter()
.append("line")
.attr("x1", function(d, i) { return r*Math.cos( parseFloat(d)/r);})
.attr("y1", function(d) { return r*Math.sin( parseFloat(d)/r) ;})
.attr("x2", function(d) { return r*Math.cos( parseFloat(d)/r) + parseFloat(d) ;})
.attr("y2", function(d) { return r*Math.sin( parseFloat(d)/r) + parseFloat(d) ;})
.attr("class", "line")
.style("stroke", function (d) {return color(d.data) ; })
.style("stroke-width", "3px");
Please i need your help.
As pointed out in the comments, the arc.centroid() function provides this functionality:
var pie = d3.layout.pie().value(function(d){ return d.value; });
var arc = d3.svg.arc().innerRadius(0).outerRadius(r);
var centers = pie(data).map(arc.centroid);
Or with a D3 selection:
var centers = [];
arcs.each(function(d) {
centers.push(arc.centroid(d));
});
Complete demo here.

Create a line connecting circles upon mouse hover

I have a scatter plot made in D3 with circles denoting each data point. Here's my code:
viz.selectAll('circle')
.data(data)
.enter()
.append('circle')
.attr("cx", function(d) {return x(d.x)})
.attr("cy", function(d) {return y(d.y)})
.attr("r", 5)
.attr("fill", function(d) {return d.color})
.on('mouseover', function(d){
console.log(d.color)
})
What I would like to do is, when a given circle is hovered on, connect all circles through a line that have the same color. How can I do this? I can get the color logged into the console, but I don't understand how I can connect all points with the same color through a line upon mouse click?
You can assign a class with color code to your circles. Use d3.selectAll to retrieve all of them on mouseover. Then retrieve their coordinates and pass the coordinates to draw d3.svg.line.
svg.selectAll(".dot")
.data(data)
.enter().append("circle")
.attr("class", function(d) {
return 'dot color-' + color(d.species).replace('#','');
})
.attr("r", 3.5)
.attr("cx", function(d) { return x(d.sepalWidth); })
.attr("cy", function(d) { return y(d.sepalLength); })
.attr("dot-color", function(d) { return color(d.species).replace('#',''); })
.style("fill", function(d) { return color(d.species); })
.on("mouseover", function() {
d3.selectAll(".color-" + $(this).attr("dot-color"))
.attr("r", 5.5);
})
.on("mouseout", function() {
d3.selectAll(".color-" + $(this).attr("dot-color"))
.attr("r", 3.5);
});
Here's an example with color hover:
http://vida.io/documents/KinEKRkSPSfStA4Eu
You can also do it without relying on a common class attribute. In the mouseover handler:
d3.selectAll('.dot')
.filter(function (dOther) { return d.color == dOther.color })
.attr('r', 3.5)

How to zoom a d3.js DotsChart instead of lineChart

i want zoom a dot chart like a line but each point are duplicated by zoom step.
g.updateCurve = function(_){
// Update the line path.
this.select(".line")
.attr("d", line);
// add each point
this.selectAll('.circle').data(data).enter().append("circle")
.attr("class", "dot")
.attr("cx", function(d) {return xScale (d.date); })
.attr("cy", function(d) {return yScale (d.ySpeed); })
.attr("r", function(d) {return rScale (d.xSpeed); });
return this;
};
how can I change for a proper zoom ?
I work on this JSFiddle
it need to costruct DOM.Circle.data before the update fonction:
g.selectAll('circle').data(data).enter().append("circle")
.attr("class", "dot");
and juste update .attr() on zoom event
// for update Attribute of line and Dots on ZoomEvent
g.updateCurve = function(){
// Update the line path.
this.select(".line")
.attr("d", line);
// add each point
this.selectAll('circle')
.attr("cx", function(d) {return xScale (d.date); })
.attr("cy", function(d) {return yScale (d.ySpeed); })
.attr("r", function(d) {return rScale (d.xSpeed); });
return this;
};
Working exemple on JSFiddle

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