d3.js static force layout

Question

I am using d3.js and would like the force layout to be NOT random every time I load up the page. I have already read over a few questions and I set the node position but th

Answer 1

Just set static x and y positions in your node objects.

var graph = {
    "nodes": [{
        "name": "1",
        "rating": 90,
        "id": 2951,
        x: 5, //Any random value
        y: 10  //Any random value
    }, {
        "name": "2",
        "rating": 80,
        "id": 654654,
        x: 15,
        y: 20
        ------------------
        -------------------
    }],
    "links": [{
        "source": 5,
        "target": 2,
        "value": 6,
        "label": "publishedOn"
    }, {
        "source": 1,
        "target": 5,
        "value": 6,
        "label": "publishedOn"
    },
    ------------------
    -------------------
}

Here is the working code snippet.

var graph = {
    "nodes": [{
        "name": "1",
        "rating": 90,
        "id": 2951,
        x: 5,
        y: 10
    }, {
        "name": "2",
        "rating": 80,
        "id": 654654,
        x: 15,
        y: 20
    }, {
        "name": "3",
        "rating": 80,
        "id": 6546544,
        x: 5,
        y: 60
    }, {
        "name": "4",
        "rating": 1,
        "id": 68987978,
        x: 55,
        y: 17
    }, {
        "name": "5",
        "rating": 1,
        "id": 9878933,
        x: 24,
        y: 70
    }, {
        "name": "6",
        "rating": 1,
        "id": 6161,
        x: 35,
        y: 10
    }],
    "links": [{
        "source": 5,
        "target": 2,
        "value": 6,
        "label": "publishedOn"
    }, {
        "source": 1,
        "target": 5,
        "value": 6,
        "label": "publishedOn"
    }, {
        "source": 4,
        "target": 5,
        "value": 4,
        "label": "containsKeyword"
    }, {
        "source": 2,
        "target": 3,
        "value": 3,
        "label": "containsKeyword"
    }, {
        "source": 3,
        "target": 2,
        "value": 4,
        "label": "publishedBy"
    }]
}


var margin = {
    top: -5,
    right: -5,
    bottom: -5,
    left: -5
};
var width = 500 - margin.left - margin.right,
    height = 400 - margin.top - margin.bottom;

var color = d3.scale.category20();

var force = d3.layout.force()
    .charge(-200)
    .linkDistance(50)
    .size([width + margin.left + margin.right, height + margin.top + margin.bottom]);

var zoom = d3.behavior.zoom()
    .scaleExtent([1, 10])
    .on("zoom", zoomed);

var drag = d3.behavior.drag()
    .origin(function(d) {
        return d;
    })
    .on("dragstart", dragstarted)
    .on("drag", dragged)
    .on("dragend", dragended);


var svg = d3.select("#map").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
    .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.right + ")")
    .call(zoom);

var rect = svg.append("rect")
    .attr("width", width)
    .attr("height", height)
    .style("fill", "none")
    .style("pointer-events", "all");

var container = svg.append("g");

//d3.json('http://blt909.free.fr/wd/map2.json', function(error, graph) {

force
    .nodes(graph.nodes)
    .links(graph.links)
    .start();

var link = container.append("g")
    .attr("class", "links")
    .selectAll(".link")
    .data(graph.links)
    .enter().append("line")
    .attr("class", "link")
    .style("stroke-width", function(d) {
        return Math.sqrt(d.value);
    });

var node = container.append("g")
    .attr("class", "nodes")
    .selectAll(".node")
    .data(graph.nodes)
    .enter().append("g")
    .attr("class", "node")
    .attr("cx", function(d) {
        return d.x;
    })
    .attr("cy", function(d) {
        return d.y;
    })
    .call(drag);

node.append("circle")
    .attr("r", function(d) {
        return d.weight * 2 + 12;
    })
    .style("fill", function(d) {
        return color(1 / d.rating);
    });


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("transform", function(d) {
        return "translate(" + d.x + "," + d.y + ")";
    });
});

var linkedByIndex = {};
graph.links.forEach(function(d) {
    linkedByIndex[d.source.index + "," + d.target.index] = 1;
});

function isConnected(a, b) {
    return linkedByIndex[a.index + "," + b.index] || linkedByIndex[b.index + "," + a.index];
}

node.on("mouseover", function(d) {

    node.classed("node-active", function(o) {
        thisOpacity = isConnected(d, o) ? true : false;
        this.setAttribute('fill-opacity', thisOpacity);
        return thisOpacity;
    });

    link.classed("link-active", function(o) {
        return o.source === d || o.target === d ? true : false;
    });

    d3.select(this).classed("node-active", true);
    d3.select(this).select("circle").transition()
        .duration(750)
        .attr("r", (d.weight * 2 + 12) * 1.5);
})

.on("mouseout", function(d) {

    node.classed("node-active", false);
    link.classed("link-active", false);

    d3.select(this).select("circle").transition()
        .duration(750)
        .attr("r", d.weight * 2 + 12);
});


function dottype(d) {
    d.x = +d.x;
    d.y = +d.y;
    return d;
}

function zoomed() {
    container.attr("transform", "translate(" + d3.event.translate + ")scale(" + d3.event.scale + ")");
}

function dragstarted(d) {
    d3.event.sourceEvent.stopPropagation();

    d3.select(this).classed("dragging", true);
    force.start();
}

function dragged(d) {

    d3.select(this).attr("cx", d.x = d3.event.x).attr("cy", d.y = d3.event.y);

}

function dragended(d) {

    d3.select(this).classed("dragging", false);
}

.node {
  stroke: #fff;
  stroke-width: 1.5px;
}

.node-active{
  stroke: #555;
  stroke-width: 1.5px;
}

.link {
  stroke: #555;
  stroke-opacity: .3;
}

.link-active {
  stroke-opacity: 1;
}

.overlay {
  fill: none;
  pointer-events: all;
}

#map{
    border: 2px #555 dashed;
    width:500px;
    height:400px;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<body>
    <div id="map"></div>
</body>