tilte sankey d3.js change color

d3.sankey = function() {
  var sankey = {},
      nodeWidth = 24,
      nodePadding = 12,
      size = [1, 1],
      nodes = [],
      links = [];

  sankey.nodeWidth = function(_) {
    if (!arguments.length) return nodeWidth;
    nodeWidth = +_;
    return sankey;
  };

  sankey.nodePadding = function(_) {
    if (!arguments.length) return nodePadding;
    nodePadding = +_;
    return sankey;
  };

  sankey.nodes = function(_) {
    if (!arguments.length) return nodes;
    nodes = _;
    return sankey;
  };

  sankey.links = function(_) {
    if (!arguments.length) return links;
    links = _;
    return sankey;
  };

  sankey.size = function(_) {
    if (!arguments.length) return size;
    size = _;
    return sankey;
  };

  sankey.layout = function(iterations) {
    computeNodeLinks();
    computeNodeValues();
    computeNodeBreadths();
    computeNodeDepths(iterations);
    computeLinkDepths();
    return sankey;
  };

  sankey.relayout = function() {
    computeLinkDepths();
    return sankey;
  };

  sankey.link = function() {
    var curvature = .8;

    function link(d) {
      var x0 = d.source.x + d.source.dx,
          x1 = d.target.x,
          xi = d3.interpolateNumber(x0, x1),
          x2 = xi(curvature),
          x3 = xi(1 - curvature),
          y0 = d.source.y + d.sy + d.dy / 2,
          y1 = d.target.y + d.ty + d.dy / 2;
      return "M" + x0 + "," + y0
           + "C" + x2 + "," + y0
           + " " + x3 + "," + y1
           + " " + x1 + "," + y1;
    }

    link.curvature = function(_) {
      if (!arguments.length) return curvature;
      curvature = +_;
      return link;
    };

    return link;
  };

  // Populate the sourceLinks and targetLinks for each node.
  // Also, if the source and target are not objects, assume they are indices.
  function computeNodeLinks() {
    nodes.forEach(function(node) {
      node.sourceLinks = [];
      node.targetLinks = [];
    });
    links.forEach(function(link) {
      var source = link.source,
          target = link.target;
      if (typeof source === "number") source = link.source = nodes[link.source];
      if (typeof target === "number") target = link.target = nodes[link.target];
      source.sourceLinks.push(link);
      target.targetLinks.push(link);
    });
  }

  // Compute the value (size) of each node by summing the associated links.
  function computeNodeValues() {
    nodes.forEach(function(node) {
      node.value = Math.max(
        d3.sum(node.sourceLinks, value),
        d3.sum(node.targetLinks, value)
      );
    });
  }

  // Iteratively assign the breadth (x-position) for each node.
  // Nodes are assigned the maximum breadth of incoming neighbors plus one;
  // nodes with no incoming links are assigned breadth zero, while
  // nodes with no outgoing links are assigned the maximum breadth.
  function computeNodeBreadths() {
    var remainingNodes = nodes,
        nextNodes,
        x = 0;

    while (remainingNodes.length) {
      nextNodes = [];
      remainingNodes.forEach(function(node) {
        node.x = x;
        node.dx = nodeWidth;
        node.sourceLinks.forEach(function(link) {
          nextNodes.push(link.target);
        });
      });
      remainingNodes = nextNodes;
      ++x;
    }

    //
    moveSinksRight(x);
    scaleNodeBreadths((size[0] - nodeWidth) / (x - 1));
  }

  function moveSourcesRight() {
    nodes.forEach(function(node) {
      if (!node.targetLinks.length) {
        node.x = d3.min(node.sourceLinks, function(d) { return d.target.x; }) - 1;
      }
    });
  }

  function moveSinksRight(x) {
    nodes.forEach(function(node) {
      if (!node.sourceLinks.length) {
        node.x = x - 1;
      }
    });
  }

  function scaleNodeBreadths(kx) {
    nodes.forEach(function(node) {
      node.x *= kx;
    });
  }

  function computeNodeDepths(iterations) {
    var nodesByBreadth = d3.nest()
        .key(function(d) { return d.x; })
        .sortKeys(d3.ascending)
        .entries(nodes)
        .map(function(d) { return d.values; });

    //
    initializeNodeDepth();
    resolveCollisions();
    for (var alpha = 1; iterations > 0; --iterations) {
      relaxRightToLeft(alpha *= .99);
      resolveCollisions();
      relaxLeftToRight(alpha);
      resolveCollisions();
    }

    function initializeNodeDepth() {
      var ky = d3.min(nodesByBreadth, function(nodes) {
        return (size[1] - (nodes.length - 1) * nodePadding) / d3.sum(nodes, value);
      });

      nodesByBreadth.forEach(function(nodes) {
        nodes.forEach(function(node, i) {
          node.y = i;
          node.dy = node.value * ky;
        });
      });

      links.forEach(function(link) {
        link.dy = link.value * ky;
      });
    }

    function relaxLeftToRight(alpha) {
      nodesByBreadth.forEach(function(nodes, breadth) {
        nodes.forEach(function(node) {
          if (node.targetLinks.length) {
            var y = d3.sum(node.targetLinks, weightedSource) / d3.sum(node.targetLinks, value);
            node.y += (y - center(node)) * alpha;
          }
        });
      });

      function weightedSource(link) {
        return center(link.source) * link.value;
      }
    }

    function relaxRightToLeft(alpha) {
      nodesByBreadth.slice().reverse().forEach(function(nodes) {
        nodes.forEach(function(node) {
          if (node.sourceLinks.length) {
            var y = d3.sum(node.sourceLinks, weightedTarget) / d3.sum(node.sourceLinks, value);
            node.y += (y - center(node)) * alpha;
          }
        });
      });

      function weightedTarget(link) {
        return center(link.target) * link.value;
      }
    }

    function resolveCollisions() {
      nodesByBreadth.forEach(function(nodes) {
        var node,
            dy,
            y0 = 0,
            n = nodes.length,
            i;

        // Push any overlapping nodes down.
        nodes.sort(ascendingDepth);
        for (i = 0; i < n; ++i) {
          node = nodes[i];
          dy = y0 - node.y;
          if (dy > 0) node.y += dy;
          y0 = node.y + node.dy + nodePadding;
        }

        // If the bottommost node goes outside the bounds, push it back up.
        dy = y0 - nodePadding - size[1];
        if (dy > 0) {
          y0 = node.y -= dy;

          // Push any overlapping nodes back up.
          for (i = n - 2; i >= 0; --i) {
            node = nodes[i];
            dy = node.y + node.dy + nodePadding - y0;
            if (dy > 0) node.y -= dy;
            y0 = node.y;
          }
        }
      });
    }

    function ascendingDepth(a, b) {
      return a.y - b.y;
    }
  }

  function computeLinkDepths() {
    nodes.forEach(function(node) {
      node.sourceLinks.sort(ascendingTargetDepth);
      node.targetLinks.sort(ascendingSourceDepth);
    });
    nodes.forEach(function(node) {
      var sy = 0, ty = 0;
      node.sourceLinks.forEach(function(link) {
        link.sy = sy;
        sy += link.dy;
      });
      node.targetLinks.forEach(function(link) {
        link.ty = ty;
        ty += link.dy;
      });
    });

    function ascendingSourceDepth(a, b) {
      return a.source.y - b.source.y;
    }

    function ascendingTargetDepth(a, b) {
      return a.target.y - b.target.y;
    }
  }

  function center(node) {
    return 0;
  }
  function ascendingDepth(a, b) {
  return b.y - a.y;
}

  function value(link) {
    return link.value;
  }

  return sankey;
};




d3.csv(text)function (error, data) {
                $body.removeClass("loading");

                d3.select("#chart").select("svg").remove();
                var units = "";
                var margin = {top: 10, right: 10, bottom: 10, left: 10},
                width = 900 - margin.left - margin.right,
                        height = 1400 - margin.top - margin.bottom;
                var formatNumber = d3.format(",0f"), // zero decimal places
                        format = function (d) {
                            return formatNumber(d) + " " + units;
                        },
                        color = d3.scale.category20();
                // append the svg canvas to the page
                var svg = d3.select("#chart").append("svg")
                        .attr("width", width + margin.left + margin.right)
                        .attr("height", height + margin.top + margin.bottom)
                        .append("g")
                        .attr("transform",
                                "translate(" + margin.left + "," + margin.top + ")");
// Set the sankey diagram properties
                var sankey = d3.sankey()
                        .nodeWidth(45)
                        .nodePadding(14)
                        .size([width, height]);
                var path = sankey.link();
                graph = {"nodes": [], "links": []};
                data.forEach(function (d) {
                    graph.nodes.push({"name": d.source});
                    graph.nodes.push({"name": d.target});
                    graph.links.push({"source": d.source, "target": d.target, "value": +d.value, "percentagem": +d.percentagem});
                });
                //this handy little function returns only the distinct / unique nodes
                graph.nodes = d3.keys(d3.nest()
                        .key(function (d) {
                            return d.name;
                        })
                        .map(graph.nodes));
                //it appears d3 with force layout wants a numeric source and target
                //so loop through each link replacing the text with its index from node
                graph.links.forEach(function (d, i) {
                    graph.links[i].source = graph.nodes.indexOf(graph.links[i].source);
                    graph.links[i].target = graph.nodes.indexOf(graph.links[i].target);
                });
                //now loop through each nodes to make nodes an array of objects rather than an array of strings
                graph.nodes.forEach(function (d, i) {
                    graph.nodes[i] = {"name": d};
                });
                sankey
                        .nodes(graph.nodes)
                        .links(graph.links)
                        .layout(32);
                // add in the links
                var link = svg.append("g").selectAll(".link")
                        .data(graph.links)
                        .enter().append("path")
                        .attr("class", "link")
                        .attr("d", path)
                        .style("stroke-width", function (d) {
                            return Math.max(1, d.dy);
                        })
                        .sort(function (a, b) {
                            return b.dy - a.dy;
                        });

                // add the link titles
                link.append("title")
                        .style()
                        .text(function (d) {
                            return "<p>Origem</p>" + "\n" +
                                    d.source.name + " → " +
                                    "<h2>Destino</h2>" + "\n" +
                                    d.target.name + "\n" + format(d.percentagem) + "%";
                        });
                // add in the nodes
                var node = svg.append("g").selectAll(".node")
                        .data(graph.nodes)
                        .enter().append("g")
                        .attr("class", "node")
                        .attr("transform", function (d) {
                            return "translate(" + d.x + "," + d.y + ")";
                        })
                        .call(d3.behavior.drag()
                                .origin(function (d) {
                                    return d;
                                })
                                .on("dragstart", function () {
                                    this.parentNode.appendChild(this);
                                })
                                .on("drag", dragmove));
                        
                // add the rectangles for the nodes
                node.append("rect")
                        .attr("height", function (d) {
                            return d.dy;
                        })
                        .attr("width", sankey.nodeWidth())
                        .style("fill", function (d) {
                            return d.color = color(d.name.replace(/ .*/, ""));
                        })
                        .style("stroke", function (d) {
                            return d3.rgb(d.color).darker(2);
                        })
                        .append("title")
                        .text(function (d) {
                            return d.name + "\n " + format(d.value);
                        });
                // add in the title for the nodes
                node.append("text")
                        .attr("x", -6)
                        .attr("y", function (d) {
                            return d.dy / 2;
                        })
                        .attr("dy", ".35em")
                        .attr("text-anchor", "end")
                        .attr("transform", null)
                        .text(function (d) {
                            return d.name;
                        })
                        .filter(function (d) {
                            return d.x < width / 2;
                        })
                        .attr("x", 6 + sankey.nodeWidth())
                        .attr("text-anchor", "start");
                // the function for moving the nodes
                function dragmove(d) {
                    d3.select(this).attr("transform",
                            "translate(" + (
                                    d.x = Math.max(0, Math.min(width - d.dx, d3.event.x))
                                    ) + "," + (
                            d.y = Math.max(0, Math.min(height - d.dy, d3.event.y))
                            ) + ")");
                    sankey.relayout();
                    link.attr("d", path);
                }
            });

var text="source,target,value,percentagem
Residentes-Minho-Lima,Trabalhadores-Cávado,252,26.44
Residentes-Minho-Lima,Trabalhadores-Ave,56,5.88
Residentes-Minho-Lima,Trabalhadores-Grande Porto,276,28.96
Residentes-Minho-Lima,Trabalhadores-Tâmega,6,0.63
Residentes-Minho-Lima,Trabalhadores-Entre Douro e Vouga,8,0.84
Residentes-Minho-Lima,Trabalhadores-Douro,25,2.62
Residentes-Minho-Lima,Trabalhadores-Alto Trás-os-Montes,16,1.68
Residentes-Minho-Lima,Trabalhadores-Algarve,15,1.57
Residentes-Minho-Lima,Trabalhadores-Baixo Vouga,19,1.99
Residentes-Minho-Lima,Trabalhadores-Baixo Mondego,18,1.89
Residentes-Minho-Lima,Trabalhadores-Pinhal Litoral,7,0.73"
        <div id="chart">
                          
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script><script>varunits="Numero";

            var margin = {top: 10, right: 10, bottom: 10, left: 10},
            width = 900 - margin.left - margin.right,
            height = 1400 - margin.top - margin.bottom;

            var formatNumber = d3.format(",.0f"), // zero decimal places
                    format = function (d) {
                        return formatNumber(d) + " " + units;
                    },
                    color = d3.scale.category20();

// append the svg canvas to the page
            var svg = d3.select("#chart").append("svg")
                    .attr("width", width + margin.left + margin.right)
                    .attr("height", height + margin.top + margin.bottom)
                    .append("g")
                    .attr("transform",
                            "translate(" + margin.left + "," + margin.top + ")");

// Set the sankey diagram properties
            var sankey = d3.sankey()
                    .nodeWidth(45)
                    .nodePadding(14)
                    .size([width, height]);

            var path = sankey.link();
            
       
                        </script>
                        <script src="scriptsankey.js" type="text/javascript"></script>

                    </div>