Develop Reference

(d3.js) How to combine dynamic force directed graph with collapsible force directed graph?

I'm trying to combine two different force directed graphs.
One is dynamic force directed graph (code from here) where I can set the thickness of the lines between nodes (and the data is defined inline); the other is collapsible force directed graph (code from a SO answer here, that uses non-tree data) where I can click the nodes to hide the children (and the data is defined from a JSON file).
I thought this should be clear enough, but I keep having problems. The JS console said that the propertyforce is undefined even though I have set its variable.
Here is the Plunker: http://plnkr.co/edit/MtOB9PGnXlNwlNj6P5NY?p=preview
And here is the collapsible graph part (full code is in Plunker)
// Combined script //
var root,
force = d3.layout.force()
.size([width, height])
.on("tick", tick);
var link = svg.selectAll(".link"),
node = svg.selectAll(".node");
d3.json("data.json", function(json) {
root = json;
//Give nodes ids and initialize variables
for(var i=0; i<root.nodes.length; i++) {
var node = root.nodes[i];
node.id = i;
node.collapsing = 0;
node.collapsed = false;
}
//Give links ids and initialize variables
for(var i=0; i<root.links.length; i++) {
var link = root.links[i];
link.source = root.nodes[link.source];
link.target = root.nodes[link.target];
link.id = i;
}
update();
});
function update() {
//Keep only the visible nodes
var nodes = root.nodes.filter(function(d) {
return d.collapsing == 0;
});
var links = root.links;
//Keep only the visible links
links = root.links.filter(function(d) {
return d.source.collapsing == 0 && d.target.collapsing == 0;
});
force
.nodes(nodes)
.links(links)
.start();
// Update the links…
link = link.data(links, function(d) { return d.id; });
// Exit any old links.
link.exit().remove();
// Enter any new links.
link.enter().insert("line", ".node")
.attr("class", "link")
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; })
.attr("marker-end", "url(#arrow)");
// Update the nodes…
node = node.data(nodes, function(d){ return d.id; }).style("fill", color);
// Exit any old nodes.
node.exit().remove();
// Enter any new nodes.
node.enter().append("circle")
.attr("class", "node")
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.attr("r", function(d) { return Math.sqrt(d.size) / 10 || 4.5; })
.style("fill", color)
.on("click", click)
.call(force.drag);
}
function tick() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
}
// Toggle children on click.
function click(d) {
if (!d3.event.defaultPrevented) {
//check if link is from this node, and if so, collapse
root.links.forEach(function(l) {
if(l.source.id == d.id) {
if(d.collapsed){
l.target.collapsing--;
} else {
l.target.collapsing++;
}
}
});
d.collapsed = !d.collapsed;
}
update();
}
// Combined end //
Without combining the two codes, it's working fine, as shown in this fiddle: https://jsfiddle.net/Lrrepn0c/
Any ideas?

How to display source nodes of a clicked target?

How can I display the source nodes names of a clicked target node in a forced directed graph using D3?
The snippet below is from some example code for directed graphs by Mike Bostock. How can I go about modifying this base code so when a node is clicked on the graph, the target values of that node is displayed on the screen (in this case I would like to display the name attributes)?
For example the 0-th element in "nodes" is:
"nodes":[
{"name":"Myriel","group":1},
...
]
And in "links" the targets are define like so:
"links":[
{"source":1,"target":0,"value":1}, // Napoleon
{"source":2,"target":0,"value":8}, // Mlle.Baptistine
{"source":3,"target":0,"value":10}, // Mme.Magloire
{"source":3,"target":2,"value":6},
{"source":4,"target":0,"value":1}, // CountessdeLo
{"source":5,"target":0,"value":1}, // Geborand
{"source":6,"target":0,"value":1}, // Champtercier
{"source":7,"target":0,"value":1}, // Cravatte
{"source":8,"target":0,"value":2}, // Count
{"source":9,"target":0,"value":1}, // OldMan
...
{"source":11,"target":0,"value":5}, // Valjean
...
]
Then clicking on the node Myriel would display:
Napoleon,Mlle.Baptistine,Mme.Magloire,CountessdeLo,Geborand,Champtercier,Cravatte,Count,OldMan,Valjean
Myriel is located here in the graph:
Below is the JavaScript code:
var width = 960,
height = 500;
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size([width, height]);
d3.json("https://gist.githubusercontent.com/mbostock/4062045/raw/9653f99dbf6050b0f28ceafbba659ac5e1e66fbd/miserables.json", function(error, graph) {
if (error) throw error;
force
.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.style("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.selectAll(".node")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", 5)
.style("fill", function(d) { return color(d.group); })
.call(force.drag)
.on("click",function(d){
var targets = graph.links.filter(function(i){
return i.target.name == d.name
});
tip.show( targets.map(function(i){ return i.source.name;}) );
});
node.append("title")
.text(function(d) { return d.name; });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
var width = 960,
height = 500;
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size([width, height]);
d3.json("https://gist.githubusercontent.com/mbostock/4062045/raw/9653f99dbf6050b0f28ceafbba659ac5e1e66fbd/miserables.json", function(error, graph) {
if (error) throw error;
force
.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.style("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.selectAll(".node")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", 5)
.style("fill", function(d) { return color(d.group); })
.call(force.drag)
.on("click",function(d){
var targets = graph.links.filter(function(i){
return i.target.name == d.name
});
tip.show( targets.map(function(i){ return i.source.name;}) );
});
node.append("title")
.text(function(d) { return d.name; });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
.node {
stroke: #fff;
stroke-width: 1.5px;
}
.link {
stroke: #999;
stroke-opacity: .6;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.0/d3.min.js"></script>

Add a click event on each node, then inside we can get all the targets by filtering the graph.links array such that we only have the elements who's target.name is the same as the clicked nodes name d.name. Once we have that you can use .map() to return the array with .source.name to give the name of those items inside targets:
.on("click",function(d) {
var targets = graph.links.filter(function(i){
return i.target.name==d.name;
});
tip.show( targets.map(function(i){ return i.source.name; }) );
});
var tip = d3.tip().attr('class', 'd3-tip').html(function(d) { return d; });
var width = 960,
height = 500;
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
svg.call(tip);
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size([width, height]);
d3.json("https://gist.githubusercontent.com/mbostock/4062045/raw/9653f99dbf6050b0f28ceafbba659ac5e1e66fbd/miserables.json", function(error, graph) {
if (error) throw error;
force
.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.style("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.selectAll(".node")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", 5)
.style("fill", function(d) { return color(d.group); })
.call(force.drag)
.on("click",function(d){
var targets = graph.links.filter(function(i){
return i.target.name == d.name
});
tip.show( targets.map(function(i){ return i.source.name;}) );
});
node.append("title")
.text(function(d) { return d.name; });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
.node {
stroke: #fff;
stroke-width: 1.5px;
}
.link {
stroke: #999;
stroke-opacity: .6;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.0/d3.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3-tip/0.6.7/d3-tip.min.js"></script>
Now for easy display of those values the d3-tip library can be used. This would be initialized for the graph like so:
var tip = d3.tip().attr('class', 'd3-tip').html(function(d) { return d; });
...
var svg = ..
svg.call(tip);
And finally the tip.show(...) function in the first code snippet will display those items on the graph.

Addition of new javascript results in graph not being recognised in d3

I've added a new peice of javascript to an old script I had to add a highlighting functionality to a force network layout. I get the information for the diagram from generated json in a rails app. The original code I've been using is here:
var width = 960,
height = 960;
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-100)
.linkDistance(530)
.size([width, height]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var endpoint = window.location.href+".json"
d3.json(endpoint, function(graph) {
force
.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.style("marker-end", "url(#suit)");
var node = svg.selectAll(".node")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", 10)
.style("fill", function(d) { return color(d.group); })
.call(force.drag)
.on('dblclick', connectedNodes);
node.append("title")
.text(function(d) { return d.name; });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
svg.append("defs").selectAll("marker")
.data(["suit", "licensing", "resolved"])
.enter().append("marker")
.attr("id", function(d) { return d; })
.attr("viewBox", "0 -5 10 10")
.attr("refX", 25)
.attr("refY", 0)
.attr("markerWidth", 6)
.attr("markerHeight", 6)
.attr("orient", "auto")
.append("path")
.attr("d", "M0,-5L10,0L0,5 L10,0 L0, -5")
.style("stroke", "#4679BD")
.style("opacity", "0.6");
//APPENDED CODE ADDED HERE
//Toggle stores whether the highlighting is on
var toggle = 0;
//Create an array logging what is connected to what
var linkedByIndex = {};
for (i = 0; i < graph.nodes.length; i++) {
linkedByIndex[i + "," + i] = 1;
};
graph.links.forEach(function (d) {
linkedByIndex[d.source.index + "," + d.target.index] = 1;
});
//This function looks up whether a pair are neighbours
function neighboring(a, b) {
return linkedByIndex[a.index + "," + b.index];
}
function connectedNodes() {
if (toggle == 0) {
//Reduce the opacity of all but the neighbouring nodes
d = d3.select(this).node().__data__;
node.style("opacity", function (o) {
return neighboring(d, o) | neighboring(o, d) ? 1 : 0.1;
});
link.style("opacity", function (o) {
return d.index==o.source.index | d.index==o.target.index ? 1 : 0.1;
});
//Reduce the op
toggle = 1;
} else {
//Put them back to opacity=1
node.style("opacity", 1);
link.style("opacity", 1);
toggle = 0;
}
}
I then tried to append further code as suggested here and simply added the following to the bottom of the script above where it is marked in capital letters
Could have been so simple.... The script worked but the added functionlity (to add highlights between nodes) didn't. An error message says:
Uncaught ReferenceError: graph is not defined
My susipicion is that it relates to the line
d3.json(endpoint, function(graph) {
and the fact that the subsequent }); is in the wrong place to encompass the new code but I've played with it and I'm not sure how to correct it
UPDATE
I've solved this. The problem was simply that I was declaring graph inside a function and the other functions couldn't access it. The solution is to put the other functions inside the function that delares it which in effect means moving the last
});
from the line
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
to the very last line. Works fine now

The answer is now given in the UPDATE section of the question

d3.js Combining the draggable network with a force directed graph

I'm trying to allow users to select and drag multiple nodes using d3's force-directed graph, but can't seem to get it to work.
There's a nice example of how to select multiple nodes and drag them here and the standard force-directed graph here.
When I tried combining the two, dragging more than one node need seems a little bit off, as in the nodes don't get dragged together but rather one gets dragged and the other selected ones wobble around it:
http://jsfiddle.net/pkerpedjiev/w4a5makd/2/
Can anybody clue me into what I'm doing wrong?
Here's the code:
var width = 960,
height = 500,
shiftKey;
var svg = d3.select("body")
.attr("tabindex", 1)
.on("keydown.brush", keydown)
.on("keyup.brush", keyup)
.each(function() { this.focus(); })
.append("svg")
.attr("width", width)
.attr("height", height);
var link = svg.append("g")
.attr("class", "link")
.selectAll("line");
var brush = svg.append("g")
.datum(function() { return {selected: false, previouslySelected: false}; })
.attr("class", "brush");
var node = svg.append("g")
.attr("class", "node")
.selectAll("circle");
graph.links.forEach(function(d) {
d.source = graph.nodes[d.source];
d.target = graph.nodes[d.target];
});
link = link.data(graph.links).enter().append("line")
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
brush.call(d3.svg.brush()
.x(d3.scale.identity().domain([0, width]))
.y(d3.scale.identity().domain([0, height]))
.on("brushstart", function(d) {
node.each(function(d) { d.previouslySelected = shiftKey && d.selected; });
})
.on("brush", function() {
var extent = d3.event.target.extent();
node.classed("selected", function(d) {
return d.selected = d.previouslySelected ^
(extent[0][0] <= d.x && d.x < extent[1][0]
&& extent[0][1] <= d.y && d.y < extent[1][1]);
});
})
.on("brushend", function() {
d3.event.target.clear();
d3.select(this).call(d3.event.target);
}));
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.nodes(graph.nodes)
.links(graph.links)
.size([width, height])
.start();
node = node.data(graph.nodes).enter().append("circle")
.attr("r", 4)
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.on("mousedown", function(d) {
if (!d.selected) { // Don't deselect on shift-drag.
if (!shiftKey) node.classed("selected", function(p) { return p.selected = d === p; });
else d3.select(this).classed("selected", d.selected = true);
}
})
.on("mouseup", function(d) {
if (d.selected && shiftKey) d3.select(this).classed("selected", d.selected = false);
})
.call(force.drag()
.on("drag", function(d) { nudge(d3.event.dx, d3.event.dy); }));
function tick() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr('cx', d.x).attr('cy', d.y);
};
force.on("tick", tick);
function nudge(dx, dy) {
node.filter(function(d) { return d.selected; })
.attr("cx", function(d) { return d.x += dx; })
.attr("cy", function(d) { return d.y += dy; })
link.filter(function(d) { return d.source.selected; })
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; });
link.filter(function(d) { return d.target.selected; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
d3.event.sourceEvent.preventDefault();
}
function keydown() {
if (!d3.event.metaKey) switch (d3.event.keyCode) {
case 38: nudge( 0, -1); break; // UP
case 40: nudge( 0, +1); break; // DOWN
case 37: nudge(-1, 0); break; // LEFT
case 39: nudge(+1, 0); break; // RIGHT
}
shiftKey = d3.event.shiftKey || d3.event.metaKey;
}
function keyup() {
shiftKey = d3.event.shiftKey || d3.event.metaKey;
}

Figured it out. The trick is to override the default force.drag behavior. By default the drag behavior labels the node being dragged as fixed and directly changes its position. This is to prevent it from being pulled by the other nodes as it is being dragged.
When multiple nodes are selected, all of them have to be fixed and we have to directly change their positions (all of px, py, x, and y). This allows us to drag multiple nodes at once. See the fiddle here:
http://jsfiddle.net/pkerpedjiev/29majy5c/2/
Along with the corresponding code:
var width = 400,
height = 500,
shiftKey;
var svg = d3.select("body")
.attr("tabindex", 1)
.on("keydown.brush", keydown)
.on("keyup.brush", keyup)
.each(function() { this.focus(); })
.append("svg")
.attr("width", width)
.attr("height", height);
var link = svg.append("g")
.attr("class", "link")
.selectAll("line");
var brush = svg.append("g")
.datum(function() { return {selected: false, previouslySelected: false}; })
.attr("class", "brush");
var node = svg.append("g")
.attr("class", "node")
.selectAll("circle");
var graph = 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graph.links.forEach(function(d) {
d.source = graph.nodes[d.source];
d.target = graph.nodes[d.target];
});
link = link.data(graph.links).enter().append("line")
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
brush.call(d3.svg.brush()
.x(d3.scale.identity().domain([0, width]))
.y(d3.scale.identity().domain([0, height]))
.on("brushstart", function(d) {
node.each(function(d) { d.previouslySelected = shiftKey && d.selected; });
})
.on("brush", function() {
var extent = d3.event.target.extent();
node.classed("selected", function(d) {
return d.selected = d.previouslySelected ^
(extent[0][0] <= d.x && d.x < extent[1][0]
&& extent[0][1] <= d.y && d.y < extent[1][1]);
});
})
.on("brushend", function() {
d3.event.target.clear();
d3.select(this).call(d3.event.target);
}));
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.nodes(graph.nodes)
.links(graph.links)
.size([width, height])
.start();
node = node.data(graph.nodes).enter().append("circle")
.attr("r", 4)
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.on("mousedown", function(d) {
if (!d.selected) { // Don't deselect on shift-drag.
if (!shiftKey) node.classed("selected", function(p) { return p.selected = d === p; });
else d3.select(this).classed("selected", d.selected = true);
}
})
.on("mouseup", function(d) {
if (d.selected && shiftKey) d3.select(this).classed("selected", d.selected = false);
})
.call(d3.behavior.drag()
.on("dragstart", function(d1) {
node.filter(function(d) { return d.selected; })
.each(function(d) { d.fixed |= 2; })
})
.on("drag", function(d1) {
node.filter(function(d) { return d.selected; })
.each(function(d) {
d.x += d3.event.dx;
d.y += d3.event.dy;
d.px += d3.event.dx;
d.py += d3.event.dy;
})
force.resume();
})
.on("dragend", function(d) {
node.filter(function(d) { return d.selected; })
.each(function(d) { d.fixed &= ~6; })
}));
function tick() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr('cx', function(d) { return d.x; }).attr('cy', function(d) { return d.y; });
};
force.on("tick", tick);
function keydown() {
shiftKey = d3.event.shiftKey || d3.event.metaKey;
}
function keyup() {
shiftKey = d3.event.shiftKey || d3.event.metaKey;
}

d3.js force layout increase linkDistance

How to increase linkDistance without affecting the node alignment,
example: http://mbostock.github.com/d3/talk/20110921/force.html
when I try to increase the circle radius and linkDistance
the it collapse
<script type="text/javascript">
var w = 1280,
h = 800,
z = d3.scale.category20c();
var force = d3.layout.force()
.size([w, h]);
var svg = d3.select("#chart").append("svg:svg")
.attr("width", w)
.attr("height", h);
svg.append("svg:rect")
.attr("width", w)
.attr("height", h);
d3.json("flare.json", function(root) {
var nodes = flatten(root),
links = d3.layout.tree().links(nodes);
force
.nodes(nodes)
.links(links)
.start();
var link = svg.selectAll("line")
.data(links)
.enter().insert("svg:line")
.style("stroke", "#999")
.style("stroke-width", "1px");
var node = svg.selectAll("circle.node")
.data(nodes)
.enter().append("svg:circle")
.attr("r", 4.5)
.style("fill", function(d) { return z(d.parent && d.parent.name); })
.style("stroke", "#000")
.call(force.drag);
force.on("tick", function(e) {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
function flatten(root) {
var nodes = [];
function recurse(node, depth) {
if (node.children) {
node.children.forEach(function(child) {
child.parent = node;
recurse(child, depth + 1);
});
}
node.depth = depth;
nodes.push(node);
}
recurse(root, 1);
return nodes;
}
</script>

Play around with the .charge parameter. It defines how much the nodes repel each other.